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In This Article Expand or collapse the "in this article" section The Evidence of Evolution

Introduction, general overviews.

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• Pests and Pathogens
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• Controlled Selection Experiments
• Domestication
• Sexual Selection
• Evolutionary Convergence and Parallelisms
• Human Evolution
• Evolution in the Fossil Record
• Transitional Fossils
• Morphological and Developmental Homologies
• Genes and Genomes
• Biogeography

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The Evidence of Evolution by Kenneth Olsen LAST REVIEWED: 12 April 2023 LAST MODIFIED: 13 January 2014 DOI: 10.1093/obo/9780199941728-0031

“ Nothing in biology makes sense except in the light of evolution .” This statement, the title of a 1973 essay by the evolutionary biologist Theodosius Dobzhansky (b. 1900–d. 1975), encapsulates the central position that evolution holds in biology. While public understanding and acceptance of evolution is notoriously low, with fewer than half of adults in countries such as the United States and Turkey accepting evolution as fact (J. D. Miller, E. C. Scott, and S. Okamoto, Public acceptance of evolution, Science 313 (2006): 765–766), the overwhelming scientific consensus is that evolution is an incontrovertible component of our planet’s history and ongoing biology. Indeed, virtually all aspects of biology can be viewed in one way or another as providing evidence of evolution. Evolution is what accounts for the signs of shared biological ancestry that appear throughout our natural world, ranging from anatomy and development, to fossils, to genome structure and gene sequences. Evolution also explains the vast number of living species on the planet, as well as their adaptations into different ecological niches. Evolution can be defined as changes in lineages of organisms over successive generations . These changes may be described at the level of genes and genetic variation, or at the level of observable traits (phenotypes). Because evolution is a process that has both shaped the history of life on Earth and continues to operate today, the lines of evidence for evolution outlined in the sections below fall into two general categories: those documenting ongoing or very recent evolution ( Evolution Caused by Human Activity , Evolution in Wild Species , Human Evolution ), and those documenting shared ancestral origins of now-diverged lineages ( Evolution in the Fossil Record , Evidence of Shared Ancestry ).

The citations in this section provide overviews of evolutionary theory and evidence for evolution. Darwin 1859 provides the foundation, albeit incomplete, for all modern evolutionary theory. Because Darwin lacked an understanding of Mendelian inheritance, he was unable to adequately explain how traits favored under natural selection could be differentially transmitted over successive generations. The rediscovery of Mendel’s laws in the early 20th century, and the subsequent integration of Darwin’s theory with population genetics, systematics, paleontology, and other disciplines, led to the “Modern Synthesis” of the mid-20th century. With some modifications (such as to incorporate insights from molecular biology), the Modern Synthesis has continued to provide a basic framework for modern evolutionary theory. Mayr 1982 provides a useful scientific retrospective on the development of the Modern Synthesis. Jacob 1977 is important in articulating the idea that evolution does not create perfect adaptations, but rather generates workable solutions with available genetic and developmental materials. Losos, et al. 2013 provides a scholarly overview of evolutionary theory. With the growth in creationist attacks on evolution in the United States in the last three decades, most contemporary overviews of evolution that are written for nonscientists are oriented to provide counterarguments to creationist objections. Coyne 2009 and Dawkins 2009 provide two such examples. Carroll 2006 focuses specifically on genetic data as evidence, while Sober 2008 develops a formal philosophical argument in support of evolution.

Carroll, S. B. 2006. The making of the fittest: DNA and the ultimate forensic record of evolution . New York: W. W. Norton.

Written for the general audience by one of the foremost researchers in the field of evolutionary developmental biology (evo-devo), this book uses lucid writing and accessible examples to explain why DNA provides clear evidence of shared common ancestry and evolution by natural selection.

Coyne, J. A. 2009. Why evolution is true . New York: Viking.

Another work for the general reader, written by an eminent evolutionary geneticist, this book provides an expansive discussion of the many diverse lines of support for evolution and the flaws in creationist arguments.

Darwin, C. 1859. On the origin of species by means of natural selection, or, the preservation of favoured races in the struggle for life . London: Murray.

The foundation of evolutionary theory. Chapters 1–4 (pp. 7–130) clearly lay out Darwin’s mechanism of evolution by natural selection. Read the first edition, as later editions include convoluted attempts to describe inheritance.

Dawkins, R. 2009. The greatest show on earth: The evidence for evolution . New York: Free Press.

Not one to suffer fools gladly, evolutionary biologist Richard Dawkins uses clear writing and colorful examples to illustrate the abundance of evidence for evolution while skewering creationist thinking.

Jacob, F. 1977. Evolution and tinkering. Science 196:1161–1166.

DOI: 10.1126/science.860134

This article is the first to widely introduce the idea that evolution proceeds through the co-option of existing parts for new functions, producing imperfect but workable adaptive solutions. Available online for purchase or by subscription.

Losos, J. B., D. A. Baum, D. J. Futuyma, H. E. Hoekstra, R. E. Lenski, and A. J. Mooreet al., eds. 2013. The Princeton guide to evolution . Princeton, NJ: Princeton Univ. Press.

Many chapters of this edited volume directly or indirectly provide evidence of evolution. Chapter I.3 (pp. 28–39, “The Evidence for Evolution,” by Gregory C. Mayer) focuses specifically on evidence of evolution.

Mayr, E. 1982. The growth of biological thought: Diversity, evolution, and inheritance . Cambridge, MA: Belknap.

An expansive work by one of the most influential evolutionary biologists of the 20th century. Chapter 12 (pp. 535–570) provides a comprehensive historical account of the development of the Modern Synthesis in the mid-20th century. Chapter 13 (pp. 571–627) examines further 20th-century developments within the paradigm of the Modern Synthesis.

Sober, E. 2008. Evidence and evolution: The logic behind the science . Cambridge, UK: Cambridge Univ. Press.

DOI: 10.1017/CBO9780511806285

Written by a philosopher of science, this book explores the epistemological underpinnings of evolutionary theory and flaws in creationist arguments based on intelligent design.

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Scientists have discovered a wealth of evidence concerning human evolution, and this evidence comes in many forms. Thousands of human fossils enable researchers and students to study the changes that occurred in brain and body size, locomotion, diet, and other aspects regarding the way of life of early human species over the past 6 million years. Millions of stone tools, figurines and paintings, footprints, and other traces of human behavior in the prehistoric record tell about where and how early humans lived and when certain technological innovations were invented. Study of human genetics show how closely related we are to other primates – in fact, how connected we are with all other organisms – and can indicate the prehistoric migrations of our species, Homo sapiens , all over the world. Advances in the dating of fossils and artifacts help determine the age of those remains, which contributes to the big picture of when different milestones in becoming human evolved.

Exciting scientific discoveries continually add to the broader and deeper public knowledge of human evolution. Find out about the latest evidence in our What’s Hot in Human Origins section.

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Lines of Evidence: The Science of Evolution

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Fossil evidence

The fossil record provides snapshots of the past which, when assembled, illustrate a panorama of evolutionary change over the past 3.5 billion years. The picture may be smudged in places and has bits missing, but fossil evidence clearly shows that life is very, very old and has changed over time through evolution.

Early fossil discoveries Scientists have long recognized fossils as evidence of past life. The ancient Greek philosopher Xenophanes found fossilized shells on dry land and concluded that the area had once been a seabed. Almost a thousand years ago, the Chinese scientist Shen Kuo made similar arguments based on fossilized remains from species that could not have lived the modern environments in which they were discovered. In the 17th century,  Nicholas Steno  noted the similarity between shark teeth and the rocks commonly known as “tongue stones,” making the argument that the stones had come from the mouths of once-living sharks. Since then, paleontologists such as Victorian England’s Mary Anning, who helped uncover the first correctly identified ichthyosaur fossil, have continued to flesh out our understanding of the diversity of ancient life forms.

Additional clues from fossils Today, few question the finding that fossils represent past life. It’s hard to look at a T. rex skeleton and conclude otherwise.  But this doesn’t mean that science is done with fossils. Paleontologists continue to learn from fossils – and not just about the anatomy of the organisms preserved.

Fossils reveal ecological relationships from the past This leaf fossil (which is a bit more than 10 million years old) shows a distinct pattern of damage – one that matches the damage to modern leaves caused by the caterpillar of the moth Stigmella heteromelis . The damage patterns are so similar and distinct from other sorts of leaf damage that, although we don’t have fossils of the ancient moth itself, we know from the leaf fossil that it must have been present in the environment and at the time that this plant lived.  Based on where this fossil was found, scientists know that the moth species has a much smaller range today than it did in the past.  The fossil also reveals that this caterpillar was parasitized by a tiny wasp, as indicated by the small circular hole (yellow arrow) made by the wasp as it exited. We observe the same parasitic relationship between wasps and S. heteromelis today.

Fossils, physiology, and behavior Fossils can also tell us about growth patterns in ancient animals. For example, this picture shows a cross-section through the skull of the dome-headed dinosaur  Stegoceras validum . The blue spaces show where blood vessels ran through the bone.  The density of blood vessels on the dome indicate that this bone was growing quickly. That, along with other lines of evidence, suggest that this fossil came from a juvenile.  In fact, the dome-head of this dinosaur species was at its most extreme in juveniles.  This (again, along with other evidence relating to the strength of the dome) suggest that the dome was not used in head-butting competitions for adult mates, and probably served some other function – perhaps helping individuals of the same species recognize one another.

• Evo Examples

Learn more about transitional features in  Understanding macroevolution through evograms , a module exploring five examples of major evolutionary transitions in the fossil record.

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Teaching About Evolution and the Nature of Science (1998)

Chapter: chapter 5: frequently asked questions about evolution and the nature of science, 5 frequently asked questions about evolution and the nature of science.

Teachers often face difficult questions about evolution, many from parents and others who object to evolution being taught. Science has good answers to these questions, answers that draw on the evidence supporting evolution and on the nature of science. This chapter presents short answers to some of the most commonly asked questions.

Definitions

What is evolution?

Evolution in the broadest sense explains that what we see today is different from what existed in the past. Galaxies, stars, the solar system, and earth have changed through time, and so has life on earth.

Biological evolution concerns changes in living things during the history of life on earth. It explains that living things share common ancestors. Over time, evolutionary change gives rise to new species. Darwin called this process "descent with modification," and it remains a good definition of biological evolution today.

What is "creation science"?

The ideas of "creation science" derive from the conviction that God created the universe—including humans and other living things—all at once in the relatively recent past. However, scientists from many fields have examined these ideas and have found them to be scientifically insupportable. For example, evidence for a very young earth is incompatible with many different methods of establishing the age of rocks. Furthermore, because the basic proposals of creation science are not subject to test and verification, these ideas do not meet the criteria for science. Indeed, U.S. courts have ruled that ideas of creation science are religious views and cannot be taught when evolution is taught.

The Supporting Evidence

How can evolution be scientific when no one was there to see it happen?

This question reflects a narrow view of how science works. Things in science can be studied even if they cannot be directly observed or experimented on. Archaeologists study past cultures by examining the artifacts those cultures left behind. Geologists can describe past changes in sea level by studying the marks ocean waves left on rocks. Paleontologists study the fossilized remains of organisms that lived long ago.

Something that happened in the past is thus not "off limits" for scientific study. Hypotheses can be made about such phenomena, and these hypotheses can be tested and can lead to solid conclusions. Furthermore, many key aspects of evolution occur in relatively short periods that can be observed directly—such as the evolution in bacteria of resistance to antibiotics.

Isn't evolution just an inference?

No one saw the evolution of one-toed horses from three-toed horses, but that does not mean that we cannot be confident that horses evolved. Science is practiced in many ways besides direct observation and experimentation. Much scientific discovery is done through indirect experimentation

and observation in which inferences are made, and hypotheses generated from those inferences are tested.

For instance, particle physicists cannot directly observe subatomic particles because the particles are too small. They must make inferences about the weight, speed, and other properties of the particles based on other observations. A logical hypothesis might be something like this: If the weight of this particle is Y , when I bombard it, X will happen. If X does not happen, then the hypothesis is disproved. Thus, we can learn about the natural world even if we cannot directly observe a phenomenon—and that is true about the past, too.

In historical sciences like astronomy, geology, evolutionary biology, and archaeology, logical inferences are made and then tested against data. Sometimes the test cannot be made until new data are available, but a great deal has been done to help us understand the past. For example, scorpionflies ( Mecoptera ) and true flies ( Diptera ) have enough similarities that entomologists consider them to be closely related. Scorpionflies have four wings of about the same size, and true flies have a large front pair of wings but the back pair is replaced by small club-shaped structures. If Diptera evolved from Mecoptera , as comparative anatomy suggests, scientists predicted that a fossil fly with four wings might be found—and in 1976 this is exactly what was discovered. Furthermore, geneticists have found that the number of wings in flies can be changed through mutations in a single gene.

Evolution is a well-supported theory drawn from a variety of sources of data, including observations about the fossil record, genetic information, the distribution of plants and animals, and the similarities across species of anatomy and development. Scientists have inferred that descent with modification offers the best scientific explanation for these observations.

Is evolution a fact or a theory?

The theory of evolution explains how life on earth has changed. In scientific terms, "theory" does not mean "guess" or "hunch'' as it does in everyday usage. Scientific theories are explanations of natural phenomena built up logically from testable observations and hypotheses. Biological evolution is the best scientific explanation we have for the enormous range of observations about the living world.

Scientists most often use the word "fact" to describe an observation. But scientists can also use fact to mean something that has been tested or observed so many times that there is no longer a compelling reason to keep testing or looking for examples. The occurrence of evolution in this sense is a fact. Scientists no longer question whether descent with modification occurred because the evidence supporting the idea is so strong.

Why isn't evolution called a law?

Laws are generalizations that describe phenomena, whereas theories explain phenomena. For example, the laws of thermodynamics describe what will happen under certain circumstances; thermodynamics theories explain why these events occur.

Laws, like facts and theories, can change with better data. But theories do not develop into laws with the accumulation of evidence. Rather, theories are the goal of science.

Don't many famous scientists reject evolution?

No. The scientific consensus around evolution is overwhelming. Those opposed to the teaching of evolution sometimes use quotations from prominent scientists out of context to claim that scientists do not support evolution. However, examination of the quotations reveals that the scientists are actually disputing some aspect of how evolution occurs, not whether evolution occurred. For example, the biologist Stephen Jay Gould once wrote that "the extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology." But Gould, an accomplished paleontologist and eloquent educator about evolution, was arguing about how evolution takes place. He was discussing whether the rate of change of species is constant and gradual or whether it takes place in bursts after long periods when little change occurs—an idea known as punctuated equilibrium. As Gould writes in response, "This quotation, although accurate as a partial citation, is dishonest in leaving out the following explanatory material showing my true purpose—to discuss rates of evolutionary change, not to deny the fact of evolution itself."

Gould defines punctuated equilibrium as follows:

Punctuated equilibrium is neither a creationist idea nor even a non-Darwinian evolutionary theory about sudden change that produces a new species all at once in a single generation. Punctuated equilibrium accepts the conventional idea that new species form over hundreds or thousands of generations and through an extensive series of intermediate stages. But geological time is so long that even a few thousand years may appear as a mere "moment" relative to the several million years of existence for most species. Thus, rates of evolution vary enormously and new species may appear to arise "suddenly" in geological time, even though the time involved would seem long, and the change very slow, when compared to a human lifetime.

Isn't the fossil record full of gaps?

Though significant gaps existed in the fossil record in the 19th century, many have been filled in. In addition, the consistent pattern of ancient to modern species found in the fossil record is strong evidence for evolution. The plants and animals living today are not like the plants and animals of the remote past. For example, dinosaurs were extinct long before humans walked the earth. We know this because no human remains have ever been found in rocks dated to the dinosaur era.

Some changes in populations might occur too rapidly to leave many transitional fossils. Also, many organisms were very unlikely to leave fossils, either because of their habitats or because they had no body parts that could easily be fossilized. However, in many cases, such as between primitive fish and amphibians, amphibians and reptiles, reptiles and mammals, and reptiles and birds, there are excellent transitional fossils.

Can evolution account for new species?

One argument sometimes made by supporters of "creation science" is that natural selection can produce minor changes within species, such as changes in color or beak size, but cannot generate new species from pre-existing species. However, evolutionary biologists have documented many cases in which new species have appeared in recent years (some of these cases are discussed in Chapter 2 ). Among most plants and animals, speciation is an extended process, and a single human observer can witness only a part of this process. Yet these observations of evolution at work provide powerful confirmation that evolution forms new species.

If humans evolved from apes, why are there still apes?

Humans did not evolve from modern apes, but humans and modern apes shared a common ancestor, a species that no longer exists. Because we shared a recent common ancestor with chimpanzees and gorillas, we have many anatomical, genetic, biochemical, and even behavioral similarities with the African great apes. We are less similar to the Asian apes—orangutans and gibbons—and even less similar to monkeys, because we shared common ancestors with these groups in the more distant past.

Evolution is a branching or splitting process in which populations split off from one another and gradually become different. As the two groups become isolated from each other, they stop sharing genes, and eventually genetic differences increase until members of the groups can no longer interbreed. At this point, they have become separate species. Through time, these two species might give rise to new species, and so on through millennia.

Doesn't the sudden appearance of all the "modern groups" of animals during the Cambrian explosion prove creationism?

During the Cambrian explosion, primitive representatives of the major phyla of invertebrate animals appeared—hard-shelled organisms like mollusks and arthropods. More modern representatives of these invertebrates appeared gradually through the Cambrian and the Ordovician periods. "Modern groups" like terrestrial vertebrates and flowering plants were not present. It is not true that "all the modern groups of animals" appeared during this period.

Also, Cambrian fossils did not appear spontaneously. They had ancestors in the Precambrian period, but because these Precambrian forms were soft-bodied, they left fewer fossils. A characteristic of the Cambrian fossils is the evolution of hard

body parts, which greatly improved the chance of fossilization. And even without fossils, we can infer relationships among organisms from biochemical information.

Religious Issues

Can a person believe in God and still accept evolution?

Many do. Most religions of the world do not have any direct conflict with the idea of evolution. Within the Judeo-Christian religions, many people believe that God works through the process of evolution. That is, God has created both a world that is ever-changing and a mechanism through which creatures can adapt to environmental change over time.

At the root of the apparent conflict between some religions and evolution is a misunderstanding of the critical difference between religious and scientific ways of knowing. Religions and science answer different questions about the world. Whether there is a purpose to the universe or a purpose for human existence are not questions for science. Religious and scientific ways of knowing have played, and will continue to play, significant roles in human history.

No one way of knowing can provide all of the answers to the questions that humans ask. Consequently, many people, including many scientists, hold strong religious beliefs and simultaneously accept the occurrence of evolution.

Aren't scientific beliefs based on faith as well?

Usually "faith" refers to beliefs that are accepted without empirical evidence. Most religions have tenets of faith. Science differs from religion because it is the nature of science to test and retest explanations against the natural world. Thus, scientific explanations are likely to be built on and modified with new information and new ways of looking at old information. This is quite different from most religious beliefs.

Therefore, "belief" is not really an appropriate term to use in science, because testing is such an important part of this way of knowing. If there is a component of faith to science, it is the assumption that the universe operates according to regularities—for example, that the speed of light will not change tomorrow. Even the assumption of that regularity is often tested—and thus far has held up well. This "faith" is very different from religious faith.

Science is a way of knowing about the natural world. It is limited to explaining the natural world through natural causes. Science can say nothing about the supernatural. Whether God exists or not is a question about which science is neutral.

Legal Issues

Why can't we teach creation science in my school?

The courts have ruled that "creation science" is actually a religious view. Because public schools must be religiously neutral under the U.S. Constitution, the courts have held that it is unconstitutional to present creation science as legitimate scholarship.

In particular, in a trial in which supporters of creation science testified in support of their view, a district court declared that creation science does not meet the tenets of science as scientists use the term ( McLean v. Arkansas Board of Education ). The Supreme Court has held that it is illegal to require that creation science be taught when evolution is taught ( Edwards v. Aguillard ). In addition, district courts have decided that individual teachers cannot advocate creation science on their own ( Peloza v. San Juan Capistrano School District and Webster v. New Lennox School District ).

Teachers' organizations such as the National Science Teachers Association, the National Association of Biology Teachers, the National Science Education Leadership Association, and many others also have rejected the science and pedagogy of creation science and have strongly discouraged its presentation in the public schools. (Statements from some of these organizations appear in Appendix C .) In addition, a coalition of religious and other organizations has noted in "A Joint Statement of Current Law" (see Appendix B ) that "in science class, [schools] may present only genuinely scientific critiques of, or evidence for, any explanation of life on earth, but not religious

critiques (beliefs unverifiable by scientific methodology)."

Some argue that "fairness" demands the teaching of creationism along with evolution. But a science curriculum should cover science, not the religious views of particular groups or individuals.

Educational Issues

If evolution is taught in schools, shouldn't creationism be given equal time?

Some religious groups deny that microorganisms cause disease, but the science curriculum should not therefore be altered to reflect this belief. Most people agree that students should be exposed to the best possible scholarship in each field. That scholarship is evaluated by professionals and educators in those fields. In science, scientists as well as educators have concluded that evolution—and only evolution—should be taught in science classes because it is the only scientific explanation for why the universe is the way it is today.

Many people say that they want their children to be exposed to creationism in school, but there are thousands of different ideas about creation among the world's people. Comparative religions might comprise a worthwhile field of study but not one appropriate for a science class. Furthermore, the U.S. Constitution states that schools must be religiously neutral, so legally a teacher could not present any particular creationist view as being more "true" than others.

Why should teachers teach evolution when they already have so many things to teach and can cover biology without mentioning evolution?

Teachers face difficult choices in deciding what to teach in their limited time, but some ideas are of central importance in each discipline. In biology, evolution is such an idea. Biology is sometimes taught as a list of facts, but if evolution is introduced early in a class and in an uncomplicated manner, it can tie many disparate facts together. Most important, it offers a way to understand the astonishing complexity, diversity, and activity of the modern world. Why are there so many different types of organisms? What is the response of a species or community to a changing environment? Why is it so difficult to develop antibiotics and insecticides that are useful for more than a decade or two? All of these questions are easily discussed in terms of evolution but are difficult to answer otherwise.

A lack of instruction about evolution also can hamper students when they need that information to take other classes, apply for college or medical school, or make decisions that require a knowledge of evolution.

Should students be given lower grades for not believing in evolution?

No. Children's personal views should have no effect on their grades. Students are not under a compulsion to accept evolution. A grade reflects a teacher's assessment of a student's understanding. If a child does not understand the basic ideas of evolution, a grade could and should reflect that lack of understanding, because it is quite possible to comprehend things that are not believed.

Can evolution be taught in an inquiry-based fashion?

Any science topic can be taught in an inquiry-oriented manner, and evolution is particularly amenable to this approach. At the core of inquiry-oriented instruction is the provision for students to collect data (or be given data when collection is not possible) and to analyze the data to derive patterns, conclusions, and hypotheses, rather than just learning facts. Students can use many data sets from evolution (such as diagrams of anatomical differences in organisms) to derive patterns or draw connections between morphological forms and environmental conditions. They then can use their data sets to test their hypotheses.

Students also can collect data in real time. For example, they can complete extended projects involving crossbreeding of fruit flies or plants to illustrate the genetic patterns of inheritance and the influence of the environment on survival. In this way, students can develop an understanding of evolution, scientific inquiry, and the nature of science.

Today many school students are shielded from one of the most important concepts in modern science: evolution. In engaging and conversational style, Teaching About Evolution and the Nature of Science provides a well-structured framework for understanding and teaching evolution.

Written for teachers, parents, and community officials as well as scientists and educators, this book describes how evolution reveals both the great diversity and similarity among the Earth's organisms; it explores how scientists approach the question of evolution; and it illustrates the nature of science as a way of knowing about the natural world. In addition, the book provides answers to frequently asked questions to help readers understand many of the issues and misconceptions about evolution.

The book includes sample activities for teaching about evolution and the nature of science. For example, the book includes activities that investigate fossil footprints and population growth that teachers of science can use to introduce principles of evolution. Background information, materials, and step-by-step presentations are provided for each activity. In addition, this volume:

• Presents the evidence for evolution, including how evolution can be observed today.
• Explains the nature of science through a variety of examples.
• Describes how science differs from other human endeavors and why evolution is one of the best avenues for helping students understand this distinction.
• Answers frequently asked questions about evolution.

Teaching About Evolution and the Nature of Science builds on the 1996 National Science Education Standards released by the National Research Council—and offers detailed guidance on how to evaluate and choose instructional materials that support the standards.

Comprehensive and practical, this book brings one of today's educational challenges into focus in a balanced and reasoned discussion. It will be of special interest to teachers of science, school administrators, and interested members of the community.

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Module 13: Theory of Evolution

Evidence for evolution, describe how the theory of evolution by natural selection is supported by evidence.

The evidence for evolution is compelling and extensive. Looking at every level of organization in living systems, biologists see the signature of past and present evolution. Darwin dedicated a large portion of his book,  On the Origin of Species , to identifying patterns in nature that were consistent with evolution, and since Darwin, our understanding has become clearer and broader.

Learning Objectives

• Outline physical evidence that supports the theory of evolution
• Outline biological evidence that supports the theory of evolution
• Refute common misconceptions about evolution

Physical Evidence

Fossils provide solid evidence that organisms from the past are not the same as those found today, and fossils show a progression of evolution. Scientists determine the age of fossils and categorize them from all over the world to determine when the organisms lived relative to each other. The resulting fossil record tells the story of the past and shows the evolution of form over millions of years (Figure 1a). For example, scientists have recovered highly detailed records showing the evolution of humans and horses (Figure 1b).

Figure 1. In this (a) display, fossil hominids are arranged from oldest (bottom) to newest (top). As hominids evolved, the shape of the skull changed. An artist’s rendition of (b) extinct species of the genus Equus reveals that these ancient species resembled the modern horse (Equus ferus) but varied in size.

Anatomy and Embryology

Figure 2. The similar construction of these appendages indicates that these organisms share a common ancestor.

Another type of evidence for evolution is the presence of structures in organisms that share the same basic form. For example, the bones in the appendages of a human, dog, bird, and whale all share the same overall construction (Figure 2) resulting from their origin in the appendages of a common ancestor. Over time, evolution led to changes in the shapes and sizes of these bones in different species, but they have maintained the same overall layout. Scientists call these synonymous parts homologous structures.

Some structures exist in organisms that have no apparent function at all, and appear to be residual parts from a past common ancestor. These unused structures without function are called vestigial structures. Some examples of vestigial structures are wings on flightless birds, leaves on some cacti, and hind leg bones in whales.

Another evidence of evolution is the convergence of form in organisms that share similar environments. For example, species of unrelated animals, such as the arctic fox and ptarmigan, living in the arctic region have been selected for seasonal white phenotypes during winter to blend with the snow and ice (Figure 3). These similarities occur not because of common ancestry, but because of similar selection pressures—the benefits of not being seen by predators.

Figure 3. The white winter coat of the (a) arctic fox and the (b) ptarmigan’s plumage are adaptations to their environments. (credit a: modification of work by Keith Morehouse)

Embryology, the study of the development of the anatomy of an organism to its adult form, also provides evidence of relatedness between now widely divergent groups of organisms. Mutational tweaking in the embryo can have such magnified consequences in the adult that embryo formation tends to be conserved. As a result, structures that are absent in some groups often appear in their embryonic forms and disappear by the time the adult or juvenile form is reached. For example, all vertebrate embryos, including humans, exhibit gill slits and tails at some point in their early development. These disappear in the adults of terrestrial groups but are maintained in adult forms of aquatic groups such as fish and some amphibians. Great ape embryos, including humans, have a tail structure during their development that is lost by the time of birth.

Biological Evidence

Biogeography.

The geographic distribution of organisms on the planet follows patterns that are best explained by evolution in conjunction with the movement of tectonic plates over geological time. Broad groups that evolved before the breakup of the supercontinent Pangaea (about 200 million years ago) are distributed worldwide. Groups that evolved since the breakup appear uniquely in regions of the planet, such as the unique flora and fauna of northern continents that formed from the supercontinent Laurasia and of the southern continents that formed from the supercontinent Gondwana. The presence of members of the plant family Proteaceae in Australia, southern Africa, and South America is best due to their appearance prior to the southern supercontinent Gondwana breaking up.

The great diversification of marsupials in Australia and the absence of other mammals reflect Australia’s long isolation. Australia has an abundance of endemic species—species found nowhere else—which is typical of islands whose isolation by expanses of water prevents species migration. Over time, these species diverge evolutionarily into new species that look very different from their ancestors that may exist on the mainland. The marsupials of Australia, the finches on the Galápagos, and many species on the Hawaiian Islands are all unique to their one point of origin, yet they display distant relationships to ancestral species on mainlands.

Molecular Biology

Like anatomical structures, the structures of the molecules of life reflect descent with modification. Evidence of a common ancestor for all of life is reflected in the universality of DNA as the genetic material and in the near universality of the genetic code and the machinery of DNA replication and expression. Fundamental divisions in life between the three domains are reflected in major structural differences in otherwise conservative structures such as the components of ribosomes and the structures of membranes. In general, the relatedness of groups of organisms is reflected in the similarity of their DNA sequences—exactly the pattern that would be expected from descent and diversification from a common ancestor.

DNA sequences have also shed light on some of the mechanisms of evolution. For example, it is clear that the evolution of new functions for proteins commonly occurs after gene duplication events that allow the free modification of one copy by mutation, selection, or drift (changes in a population’s gene pool resulting from chance), while the other copy continues to produce a functional protein.

Evolution—It’s a Thing

This video defines evolution and discusses several varieties of evidence that support the Theory of Evolution:

Misconceptions of Evolution

Although the theory of evolution generated some controversy when it was first proposed, it was almost universally accepted by biologists, particularly younger biologists, within 20 years after publication of  On the Origin of Species . Nevertheless, the theory of evolution is a difficult concept and misconceptions about how it works abound.

Evolution Is Just a Theory

Critics of the theory of evolution dismiss its importance by purposefully confounding the everyday usage of the word “theory” with the way scientists use the word. In science, a “theory” is understood to be a body of thoroughly tested and verified explanations for a set of observations of the natural world. Scientists have a theory of the atom, a theory of gravity, and the theory of relativity, each of which describes understood facts about the world. In the same way, the theory of evolution describes facts about the living world. As such, a theory in science has survived significant efforts to discredit it by scientists. In contrast, a “theory” in common vernacular is a word meaning a guess or suggested explanation; this meaning is more akin to the scientific concept of “hypothesis.” When critics of evolution say evolution is “just a theory,” they are implying that there is little evidence supporting it and that it is still in the process of being rigorously tested. This is a mischaracterization.

Individuals Evolve

Evolution is the change in genetic composition of a population over time, specifically over generations, resulting from differential reproduction of individuals with certain alleles. Individuals do change over their lifetime, obviously, but this is called development and involves changes programmed by the set of genes the individual acquired at birth in coordination with the individual’s environment. When thinking about the evolution of a characteristic, it is probably best to think about the change of the average value of the characteristic in the population over time. For example, when natural selection leads to bill-size change in medium-ground finches in the Galápagos, this does not mean that individual bills on the finches are changing. If one measures the average bill size among all individuals in the population at one time and then measures the average bill size in the population several years later, this average value will be different as a result of evolution. Although some individuals may survive from the first time to the second, they will still have the same bill size; however, there will be many new individuals that contribute to the shift in average bill size.

Organisms Evolve on Purpose

Statements such as “organisms evolve in response to a change in an environment” are quite common, but such statements can lead to two types of misunderstandings. First, the statement must not be understood to mean that individual organisms evolve. The statement is shorthand for “a population evolves in response to a changing environment.” However, a second misunderstanding may arise by interpreting the statement to mean that the evolution is somehow intentional. A changed environment results in some individuals in the population, those with particular phenotypes, benefiting and therefore producing proportionately more offspring than other phenotypes. This results in change in the population if the characteristics are genetically determined.

It is also important to understand that the variation that natural selection works on is already in a population and does not arise in response to an environmental change. For example, applying antibiotics to a population of bacteria will, over time, select a population of bacteria that are resistant to antibiotics. The resistance, which is caused by a gene, did not arise by mutation because of the application of the antibiotic. The gene for resistance was already present in the gene pool of the bacteria, likely at a low frequency. The antibiotic, which kills the bacterial cells without the resistance gene, strongly selects individuals that are resistant, since these would be the only ones that survived and divided. Experiments have demonstrated that mutations for antibiotic resistance do not arise as a result of antibiotic.

In a larger sense, evolution is not goal directed. Species do not become “better” over time; they simply track their changing environment with adaptations that maximize their reproduction in a particular environment at a particular time. Evolution has no goal of making faster, bigger, more complex, or even smarter species, despite the commonness of this kind of language in popular discourse. What characteristics evolve in a species are a function of the variation present and the environment, both of which are constantly changing in a non-directional way. What trait is fit in one environment at one time may well be fatal at some point in the future. This holds equally well for a species of insect as it does the human species.

Evolution Explains the Origin of Life

It is a common misunderstanding that evolution includes an explanation of life’s origins. Conversely, some of the theory’s critics believe that it cannot explain the origin of life. The theory does not try to explain the origin of life. The theory of evolution explains how populations change over time and how life diversifies the origin of species. It does not shed light on the beginnings of life including the origins of the first cells, which is how life is defined. The mechanisms of the origin of life on Earth are a particularly difficult problem because it occurred a very long time ago, and presumably it just occurred once. Importantly, biologists believe that the presence of life on Earth precludes the possibility that the events that led to life on Earth can be repeated because the intermediate stages would immediately become food for existing living things.

However, once a mechanism of inheritance was in place in the form of a molecule like DNA either within a cell or pre-cell, these entities would be subject to the principle of natural selection. More effective reproducers would increase in frequency at the expense of inefficient reproducers. So while evolution does not explain the origin of life, it may have something to say about some of the processes operating once pre-living entities acquired certain properties.

In Summary: Evidence for Evolution

Since Darwin developed his ideas on descent with modification and the pressures of natural selection, a variety of evidence has been gathered supporting the theory of evolution. Fossil evidence shows the changes in lineages over millions of years, such as in hominids and horses. Studying anatomy allows scientists to identify homologous structures across diverse groups of related organisms, such as leg bones. Vestigial structures also offer clues to common ancestors. Using embryology, scientists can identify common ancestors through structures present only during development and not in the adult form.

Biogeography offers further clues about evolutionary relationships. The presence of related organisms across continents indicates when these organisms may have evolved. For example, some flora and fauna of the northern continents are similar across these landmasses but distinct from that of the southern continents. Islands such as Australia and the Galapagos chain often have unique species that evolved after these landmasses separated from the mainland. Finally, molecular biology provides data supporting the theory of evolution. In particular, the universality of DNA and near universality of the genetic code for proteins shows that all life once shared a common ancestor. DNA also provides clues into how evolution may have happened. Gene duplications allow one copy to undergo mutational events without harming an organism, as one copy continues to produce functional protein.

Many misconceptions exist about the theory of evolution—including some perpetuated by critics of the theory. First, evolution as a scientific theory means that it has years of observation and accumulated data supporting it. It is not “just a theory” as a person may say in common vernacular.

Another misconception is that individuals evolve, though in fact it is populations that evolve over time. Individuals simply carry mutations. Furthermore, these mutations neither arise on purpose nor do they arise in response to an environmental pressure. Instead, mutations in DNA happen spontaneously and are already present in individuals of a population when a selective pressure occurs. Once the environment begins to favor a particular trait, then those individuals already carrying that mutation will have a selective advantage and are likely to survive better and outproduce others without the adaptation.

Finally, the theory of evolution does not in fact address the origins of life on this planet. Scientists believe that we cannot, in fact, repeat the circumstances that led to life on Earth because at this time life already exists. The presence of life has so dramatically changed the environment that the origins cannot be totally produced for study.

Check Your Understanding

Answer the question(s) below to see how well you understand the topics covered in the previous section. This short quiz does  not  count toward your grade in the class, and you can retake it an unlimited number of times.

Use this quiz to check your understanding and decide whether to (1) study the previous section further or (2) move on to the next section.

• Introduction to Evidence for Evolution. Authored by : Shelli Carter and Lumen Learning. Provided by : Lumen Learning. License : CC BY: Attribution
• Biology. Provided by : OpenStax CNX. Located at : http://cnx.org/contents/[email protected] . License : CC BY: Attribution . License Terms : Download for free at http://cnx.org/contents/[email protected]
• Evolution: It's a Thing - Crash Course Biology #20. Authored by : CrashCourse. Located at : https://youtu.be/P3GagfbA2vo . License : All Rights Reserved . License Terms : Standard YouTube License

Evidence of the Evolutionary Process Essay

Introduction, how the concept of ladder of progress took hold, references:.

Evolution is interpreted as the progressive change or survival of the fittest. Biologists and paleontologists however now believed in a gradual change of form to a different one through modification (Erikson, 157). Darwin did not use such terms in his book “Origin of species”. He believed in natural selection. The biologist Gould had used the terms “ladder of progressive evolutionary forms”. He had visualized the sequential change of parts of the body just as man evolved from the ape. The ladder of progress was a misnomer according to Gould (Erikson, 157)

This ladder tells us that evolution has produced changes favorable to the species (like climbing a ladder) and has done it progressively in small proportions. With each change needed for adaptation, the species has become better and better. Various methods have provided the evidence for this ladder of progress. The unearthing of fossils and their study, biogeography which informs us of similar species of trees and animals in various parts of the world and the reasons for such an eventuality, embryology and the study of the remaining vestigial structures in animals and human beings are some of the methods used to collect evidence of the evolutionary progress.

Donald Prothero believed that in the ladder of progress of life, new forms of animals and insects just occurred in the next generation (Wells, Evolution News). He had not believed that genetic changes or mutations in the gene governing that part of the body could be the cause of the changes. His theory was that the regulatory or Hox genes changed to produce the new forms. Prothero had ignored the development of the new science of developmental genetics (Wells, Evolution News).

Neil Shubin believed that in the very early days, there was plenty of vegetation and plants close to the ocean which had a large number of fish which grew larger and were predators for food (Shubin, WGBH). As the number of predators grew, the fish which were finding it difficult to survive decided to escape from the ocean and moved on to the land nearby. These fish developed the characteristics required to survive on land like limbs, vertebral column and development of skull with brains. Neil Shubin disliked using the term “ladder of progress”. He preferred to call it evolutionary stages. Modern biologists had compared the fin to an arm. The bones that the human being had were already seen in fish living in fresh water streams (Shubin, WGBH).

In biogeography, continental drift and taxonomy had explained the presence of similar plants in the same species in different continents (Coyne, 97). This was possible by convergent evolution. Adaptation of different animals in the same environment produced similar features. The polar bear and the snow owl were both white in correspondence with the color of snow where they live. Speciation is the process by which a common ancestor gives rise to different descendants.

Adaptation allowed some features to be changed. Geography explains biological conservation too. Islands had plants and animals which were different from the same species elsewhere due to their adaptation. These produced fragile ecosystems as they did not have competitors. Natural selection had made them defenseless. This reminds us of zoo animals. Humans were the ones who destroyed these ecosystems by burning the forests and bringing new animals and fruits into the place.

The theory of natural selection of Darwin had created widespread debate over the years but now the fact has been understood. There was randomness and lawfulness in the selection. The unwanted or unfit or unhealthy plants or animals were killed thus fitter ones were promoted (Coyne, 126). In this lawfulness, the selection weeded out the bad and kept the good. In randomness mutations did not ensure variations which were useful to the species; they were just random errors of DNA replication, some harmful and some beneficial. Current needs could not always be met. The right genetic variation in the form of mutations enabled the species to adapt and this was heritability. Everything did not happen by chance as some biologists claimed. Each stage of evolution saw a small change in trait (Coyne, 130). This evolution was usually potentially beneficial to the species.

Biologists had rarely found a step in evolution of adaptation that was not beneficial. The reproduction process also assisted evolution. Reproduction, not merely survival, was what determined the transfer of a gene into the next generation and ensured the genetic presence in the gene pool. When a person was older, the same genes could cause the production of wrinkles and enlarged prostate. We understand that natural selection also promoted reproduction. Adaptations always benefited the species involved and no other species. However the benefit part was not always true. Male lions or bonobo apes killed the offspring helping them get the females back for reproduction but the species as a whole suffered when numbers decreased.

Evolution was not always totally dependent on natural selection. It could also be defined as a change in the alleles of a population. The human being who had two copies of each gene got one from the father and one from the mother. In reproduction one of the alleles of the father united with another from the mother. This was why the child obtained features of both parents. In the process, one allele was lost. Over generations or following evolution, the proportion of various alleles differed. New mutations occurred and some genes in this random process got fixed in the population while others were lost. Genetic drift occurred. This was the “random change in the frequency of genes” (Coyne, 134).

This genetic drift usually occurred in communities which did not marry outside. Evolution was therefore a process that occurred due to natural selection and genetic drift. However genetic drift could not produce adaptation (Coyne, 135). Variations in the protein sequence of DNA or molecular evolution which did not produce harmful effects could mostly be from genetic drift. Mutations in the pseudogenes did not affect the individual (Coyne, 135). Biologists though have not ended their debate on genetic drift and natural selection.

Now artificial selection could produce new plants and animals with specific good qualities. This was breeding. Grapes that were tasty, sweet and seedless had been developed through scientific knowledge by selecting the variations from different plants. This process did not depend on adaptation but depended on the human desire to have this fruit.

Evolution through the test-tube has produced babies and cloned similar looking “mother and child” animals (Dolly and her daughter sheep). The process was allowed to happen naturally in the laboratory (Coyne, 139). Adaptive mutations had occurred in the laboratory too. Complex biochemical pathways were involved. Natural selection had caused the evolution of complex interwoven biochemical systems where each part was dependent on the other even though biologists had debated on the point. Selection also led to expression of new features by modifying the existing ones (Coyne, 140).

The use of antibiotics and specific treatment has also triggered natural selection. This has caused resistance to bacteria and viruses. Newer generations of these medicines needed to be discovered to overcome the resistant strains of bacteria and viruses like the AIDS virus. Changes caused by humans have produced changes in the environment. Natural selection in the wild was often poor (Coyne, 143).

Transitional forms could provide the evidence about evolution (Coyne, p. 36). They were those forms which occurred between two organisms different from each other. However these forms had not been identified. The microevolution was possible according to creationists but the idea of macroevolution was rejected by them. Ideas had been propagated that missing links were those forms which could give rise to two species as hypothesized. Birds had been found to have similarities to reptiles. The dinosaur was found to be the progenitor of both. Several species which had reptile-like and bird-like features had been found to have sprouted from this lineage.

Before this period 390 million years ago, fish were the only vertebrates. Fossils 375 million years old could have shown the inter-linking forms. The fossil Tiktaalik Roseae (seen on the next page) informed us about how the vertebrate amphibian came to be. It was a wonder how the lobe-finned fish came to be the amphibian. The Tiktaalik had sturdy ribs which allowed respiration and sturdy bones which were in place of the tiny bones of fish but placed in similar positions. It was adapted to live on land and swim in shallow waters. The legs constituted the leg and fin respectively. Tiktaalik could breathe atmospheric air while in shallow water but biologists found that it was not ready yet to survive on land.

The Archaeopteryx lithographica discovered in Germany was believed to be the link between the fish and the reptile (See picture on next page). The Sinornothosaurus milleni was the Chinese bird-lizard which had feathers on its body which did not help it fly (see next page). The Mei Long was a fossil which was a feathered dinosaur of small size sleeping with its head under the wings. With younger fossils more changes pointing to the evolutionary patterns of the bird breast bone were seen. Whales had ancestors who were living on the land. Fossils were evidence of evolutionary transitions (Coyne, 57). These forms had been placed between the ancestor and modern animals. The process involved a remodelling of the features in the ancestral animal into those of the new one.

Vestigial organs and behavioral traits also formed evidence of evolutionary changes or palimpsests. Molecular level palimpsests were now available with the ability to read the sequences of DNA. Palimpsests were strong evidence of evolution (Coyne, 60). The genes informed us that behaviors or anatomical features, which were found unnecessary for functioning with evolution, were usually inactivated rather than totally cut off. These could be termed dead genes (Coyne, 70). A good example was the wings of the ostrich and other flightless birds which were still remaining but not used for flying. Even the dormant genes could become active in expression when a developmental problem arises. Humans were believed to have about 2000 pseudogenes among their 30000.

As time flew even the vestiges could disappear. The Mediterranean mole rat had almost totally lost its eye as it lived underground all its life. The vestige of the eye was under a skinfold and it did not form images at all. Human vestiges included the appendix which did not seem to have any active function in the gastrointestinal system and the coccyx which reminded us of the tail our ancestors could have had. The arrector pili muscle which caused the hairs to stand up in goosebumps was another (See next page). This muscle in its well-developed form could have been used for raising the fur for insulation against the cold and threats. We can remember the cat’s “hair-raising” experiences.

“Fossil records, biogeography, embryology and vestigial structures” were evidences of evolution (Coyne, 242). Predictions which could be investigated in research and tested successfully in the laboratory were positive evidence of the evolutionary process. The fossils, the DNA sequences, the organs studied have all contributed to the expansive knowledge of evolution. Darwin’s ideas about natural selection had been verified and found correct by various researchers. However the debate on genetic drift and natural selection had not been ended by biologists. Adaptation occurred to the advantage of the species and never to destroy it.

Many questions remained as to how females selected their male partners. Did they look for good genes? The extent of the role of genetic drift in DNA evolution had to be still further determined. The direct line to Homo sapiens if any had yet to be found. The Cambrian “explosion of life” whereby many new animals appeared within a few years had to be investigated further for the causes. The ladder of progress informed us about the evolutionary process which had occurred over the centuries and was telling that more was to happen.

Coyne, A.J. Why evolution is true. Oxford University Press. New York (2009).

Erikson, M. Science, culture and society: understanding science in the 21 st century . Polity Press. Cambridge, UK (2005).

Shubin, N, and Daeschler, T. How fish came ashore. Web.

Wells, J. Donald Prothero’s Imaginary Evidence for Evolution. 2009. Web.

• Chicago (A-D)
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IvyPanda. (2022, March 25). Evidence of the Evolutionary Process. https://ivypanda.com/essays/evidence-of-the-evolutionary-process/

"Evidence of the Evolutionary Process." IvyPanda , 25 Mar. 2022, ivypanda.com/essays/evidence-of-the-evolutionary-process/.

IvyPanda . (2022) 'Evidence of the Evolutionary Process'. 25 March.

IvyPanda . 2022. "Evidence of the Evolutionary Process." March 25, 2022. https://ivypanda.com/essays/evidence-of-the-evolutionary-process/.

1. IvyPanda . "Evidence of the Evolutionary Process." March 25, 2022. https://ivypanda.com/essays/evidence-of-the-evolutionary-process/.

Bibliography

IvyPanda . "Evidence of the Evolutionary Process." March 25, 2022. https://ivypanda.com/essays/evidence-of-the-evolutionary-process/.

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Study reveals insights into protein evolution

by Marcy de Luna, Rice University

Rice University's Peter Wolynes and his research team have unveiled a breakthrough in understanding how specific genetic sequences, known as pseudogenes, evolve. Their paper was published May 13 in the Proceedings of the National Academy of Sciences .

Led by Wolynes, the D.R. Bullard-Welch Foundation Professor of Science, professor of chemistry, biosciences and physics and astronomy and co-director of the Center for Theoretical Biological Physics (CTBP), the team focused on deciphering the complex energy landscapes of de-evolved, putative protein sequences corresponding to pseudogenes.

Pseudogenes are segments of DNA that once encoded proteins but have since lost their ability to do so due to sequence degradation—a phenomenon referred to as devolution. Here, devolution represents an unconstrained evolutionary process that occurs without the usual evolutionary pressures that regulate functional protein-coding sequences.

Despite their inactive state, pseudogenes offer a window into the evolutionary journey of proteins.

"Our paper explains that proteins can de-evolve," Wolynes said. "A DNA sequence can, by mutations or other means, lose the signal that tells it to code for a protein. The DNA continues to mutate but does not have to lead to a sequence that can fold."

The researchers studied junk DNA in a genome that has de-evolved. Their research revealed that a mutation accumulation in pseudogene sequences typically disrupts the native network of stabilizing interactions, making it challenging for these sequences, if they were to be translated, to fold into functional proteins.

However, the researchers observed instances where certain mutations unexpectedly stabilized the folding of pseudogenes at the cost of altering their previous biological functions.

They identified specific pseudogenes, such as cyclophilin A, profilin-1 and small ubiquitin-like modifier 2 protein, where stabilizing mutations occurred in regions crucial for binding to other molecules and other functions, suggesting a complex balance between protein stability and biological activity .

Moreover, the study highlights the dynamic nature of protein evolution as some previously pseudogenized genes may regain their protein-coding function over time despite undergoing multiple mutations.

Using sophisticated computational models, the researchers interpreted the interplay between physical folding landscapes and the evolutionary landscapes of pseudogenes. Their findings provide evidence that the funnel-like character of folding landscapes comes from evolution.

"Proteins can de-evolve and have their ability to fold compromised over time due to mutations or other means," Wolynes said. "Our study offers the first direct evidence that evolution is shaping the folding of proteins."

Along with Wolynes, the research team includes lead author and applied physics graduate student Hana Jaafari; CTBP postdoctoral associate Carlos Bueno; University of Texas at Dallas graduate student Jonathan Martin; Faruck Morcos, associate professor in the Department of Biological Sciences at UT-Dallas; and CTBP biophysics researcher Nicholas P. Schafer.

The implications of this research extend beyond theoretical biology with potential applications in protein engineering, Jaafari said.

"It would be interesting to see if someone at a lab could confirm our results to see what happens to the pseudogenes that were more physically stable," Jaafari said. "We have an idea based on our analysis, but it'd be compelling to get some experimental validation."

Journal information: Proceedings of the National Academy of Sciences

Provided by Rice University

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