Evolution A change in successive generations of organisms, due to random mutation and changes in the organisms’ surroundings

Evolution takes place through a set of processes including: mutation adaptation natural selection extinction

Many factors can cause a change in a gene over time. Mutation Genetic mutations & variety produced by sexual reproduction allow for diversity within a given population. Many factors can cause a change in a gene over time.

Mutation Mutations are important in how populations change over time because they result in genetic changes to the gene pool.

Mutations are inheritable changes because a mutation is a change in the DNA code

Mutation = change in DNA Mutations can be: favorable change or adaptation in genetic information that improves a species’ ability to exist in its environment

Mutation = change in DNA Mutations can be: unfavorable change that does not improve a species’ ability to exist in its environment.

Mutation = change in DNA Mutations can be: changes in the genetic information that neither harms nor helps the species.

Adaptation Adaptations are structures, functions, or behaviors that enable a species to survive.

Adaptation Depending on the rate of adaptation, the rate of reproduction, and the environmental factors present, structural adaptations may take millions of years to develop.

Activity: How Handy? The Human Hand Adaptations… Activity: How Handy? The Human Hand

Figure 13.1C The voyage of the Beagle (1831–1836). For the Discovery Video Charles Darwin, go to Animation and Video Files.

DARWIN’S PHRASE FOR EVOLUTION: “Descent with Modification” He meant that present-day species arose from a succession of ancestors. Descendents of ancient ancestors that spread into new environments and accumulated diverse modifications, or adaptations that allowed them fit into specific ways of life. Copyright © 2009 Pearson Education, Inc.

Introduction: Clown, Fool, or Simply Well Adapted? What is an adaptation? Adaptations are behaviors, structures or functions that enable a species to survive. Adaptations can be behaviors (for example, the swaying of the leaf insect), structures (for example, mosquito mouthparts; cocklebur spines), biochemical and physiological modifications (for example, the booby’s salt glands) that enhance an organism’s ability to survive and reproduce in its environment. Copyright © 2009 Pearson Education, Inc.

Campbell, Neil A., Jane B. Reece, Martha R. Taylor, Eric J. Simon, Biology: Concepts & Connections, 5th ed., Figure 13.5A Camouflage as an example of evolutionary adaptation; a leaf mantid in Costa Rica. The leaf insect has a body shape, coloration, and swaying movement that enable it to avoid predation as it feeds on plant leaves.

Figure 17.10B Cockleburs fruits may be carried by animal fur. Cockleburs produce a spiny fruit that attaches to animal fur, dispersing the seeds in their environment.

Haltere Campbell, Neil A., Jane B. Reece, Martha R. Taylor, Eric J. Simon, Biology: Concepts & Connections, 5th ed., Figure 18.12F A mosquito Female mosquitoes can sense and find warm-blooded hosts and have piercing, sucking mouthparts that allow them to suck the host's blood.

Blue-footed boobies have a streamlined body and bill, allowing them to swim well. They have two specialized glands, one that secretes oil at the base of the tail to keep their plumage waterproof, and another in the eye socket that secretes salt to maintain healthy levels.

Blue-footed boobies have a streamlined body and bill, allowing them to swim well. They have two specialized glands, one that secretes oil at the base of the tail to keep their plumage waterproof, and another in the eye socket that secretes salt to maintain healthy levels.

Blue-footed boobies have a streamlined body and bill, allowing them to swim well. They have two specialized glands, one that secretes oil at the base of the tail to keep their plumage waterproof, and another in the eye socket that secretes salt to maintain healthy levels.

CHARLES DARWIN: Father of Evolution Copyright © 2009 Pearson Education, Inc.

Jean Baptiste Lamarck: Mechanism of Evolution Lamarkians would say: Use or disuse Inheritance of acquired characteristics Example…giraffes STRETCH THEIR NECKS BY REACHING and SO THEY HAVE BABIES WITH LONGER NECKS. Jean Baptiste Lamarck suggested that life on Earth evolves. He proposed a mechanism of use and disuse and inheritance of acquired characteristics: that by using or not using its body parts, an individual changes and passes on those changes to its offspring. Student Misconceptions and Concerns 1. Students often believe that Charles Darwin was the first to suggest that life evolves: the early contributions by Greek philosophers such as Anaximander and the work of Jean Baptiste de Lamarck are unappreciated. Consider emphasizing this earlier work. 2. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. Teaching Tips 1. Consider beginning your unit on evolution by asking each student to explain how a particular adaptation evolved. The evolution of flight in birds is a good example. Reviewing these student explanations can provide great insight into the misconceptions that students may bring to the class. 2. Many resources related to Charles Darwin are available on the Internet. The following are only a few examples: www.ucmp.berkeley.edu/history/evolution.html and www.natcenscied.org are extensive sites rich with details and references. www.literature.org/authors/darwin-charles/ includes the texts of The Voyage of the Beagle, The Origin of Species first and sixth editions, and The Descent of Man. http://williamcalvin.com/bookshelf/down_hse.htm includes details of Charles Darwin’s home. www.talkorigins.org is an extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins. Copyright © 2009 Pearson Education, Inc.

Charles Lyell: Father of Geology Charles Lyell: Father of Geology Principles of Geology Lyell’s Principles of Geology suggested that natural forces have gradually changed and continue to change the Earth’s surface. Student Misconceptions and Concerns 1. Students often believe that Charles Darwin was the first to suggest that life evolves: the early contributions by Greek philosophers such as Anaximander and the work of Jean Baptiste de Lamarck are unappreciated. Consider emphasizing this earlier work. 2. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. Teaching Tips 1. Consider beginning your unit on evolution by asking each student to explain how a particular adaptation evolved. The evolution of flight in birds is a good example. Reviewing these student explanations can provide great insight into the misconceptions that students may bring to the class. 2. Many resources related to Charles Darwin are available on the Internet. The following are only a few examples: www.ucmp.berkeley.edu/history/evolution.html and www.natcenscied.org are extensive sites rich with details and references. www.literature.org/authors/darwin-charles/ includes the texts of The Voyage of the Beagle, The Origin of Species first and sixth editions, and The Descent of Man. http://williamcalvin.com/bookshelf/down_hse.htm includes details of Charles Darwin’s home. www.talkorigins.org is an extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins. Copyright © 2009 Pearson Education, Inc.

Lynell’s view: Formation of Sedimentary Rock

EARTH is VERY, VERY OLD! Darwin realized Earth was very, VERY, VERY, VERY old & that, over time (LOTS OF TIME), present day species have arisen from ancestral species by natural processes sedimentary rock is very old – therefore the species that are represented in this rock must also be old. Most fossils are found in sedimentary rock. Older fossils will be found below younger fossils.

At the age of 22, Darwin joined a 5 year expedition aboard the HMS Beagle to map the coast of South America…not all who wander are lost! Great Britain Europe North America ATLANTIC OCEAN Africa PACIFIC OCEAN Brazil Equator The Galápagos Islands PACIFIC OCEAN South America Pinta Genovesa Australia Marchena Equator Santiago Cape of Good Hope Daphne Islands Andes Figure 13.1C The voyage of the Beagle (1831–1836). In 1831, Darwin joined the Beagle as the ship’s naturalist. He spent 5 years on the ship, which circumnavigated the globe, and he charted the South American coast. Argentina Fernandina Pinzón Tasmania Isabela Santa Cruz Cape Horn New Zealand Santa Fe San Cristobal 40 km Florenza Española 40 miles

Darwin’s Idea of Natural Selection Darwin observed that Organisms vary in many traits More offspring produced than the environment can support Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Individuals with traits that increase their chance of surviving & reproducing leave more offspring As a result, favorable traits accumulate in a population over generations Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Darwin found convincing evidence for his ideas in the results of artificial selection, the selective breeding of domesticated plants and animals Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

Terminal bud Lateral buds Cabbage Brussels sprouts Flower clusters Leaves Kale Cauliflower Figure 13.2 Artificial selection: different vegetables produced by selecting variations in different parts of the plant. A student took a good look at this figure and exclaimed, “All the vegetables I hate are the same species!” Stem Wild mustard Flowers and stems Broccoli Kohlrabi

Artificial Selection: Dog Breeding German shepherd Yorkshire terrier English springer spaniel Mini-dachshund Golden retriever Hundreds to thousands of years of breeding (artificial selection) Ancestral dog

13.1 A sea voyage helped Darwin frame his theory of evolution In 1859, Darwin published On the Origin of Species by Means of Natural Selection, presenting a strong, logical explanation of descent with modification, evolution by the mechanism of natural selection Student Misconceptions and Concerns 1. Students often believe that Charles Darwin was the first to suggest that life evolves: the early contributions by Greek philosophers such as Anaximander and the work of Jean Baptiste de Lamarck are unappreciated. Consider emphasizing this earlier work. 2. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. Teaching Tips 1. Consider beginning your unit on evolution by asking each student to explain how a particular adaptation evolved. The evolution of flight in birds is a good example. Reviewing these student explanations can provide great insight into the misconceptions that students may bring to the class. 2. Many resources related to Charles Darwin are available on the Internet. The following are only a few examples: www.ucmp.berkeley.edu/history/evolution.html and www.natcenscied.org are extensive sites rich with details and references. www.literature.org/authors/darwin-charles/ includes the texts of The Voyage of the Beagle, The Origin of Species first and sixth editions, and The Descent of Man. http://williamcalvin.com/bookshelf/down_hse.htm includes details of Charles Darwin’s home. www.talkorigins.org is an extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Note these important points Individuals do not evolve: populations evolve Natural selection can amplify or diminish only heritable traits; acquired characteristics cannot be passed on to offspring Evolution is not goal directed and does not lead to perfection; favorable traits vary as environments change Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Will natural selection act on variation in hair style in a human population? No; hair style is not a heritable trait. Some bright students may point out that hair length is correlated to heritable traits. For example, men who are going bald are more likely to shave their heads. Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Will natural selection act on tongue rolling in a human population? (Note: Tongue rolling is an inherited trait, caused by a dominant allele) Likely no—ability to roll the tongue likely has no fitness benefits. Ask students if they chose their boyfriends/girlfriends based on their tongue-rolling ability. If students can propose fitness correlation, they can legitimately suggest that natural selection will act on this trait. Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.

13.2 Darwin proposed natural selection as the mechanism of evolution Will natural selection act on eye number in a human population? No; there is no variation in eye number in a human population. Virtually everyone has two eyes. Student Misconceptions and Concerns 1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures because of want or need. Evolution is a passive process in which the environment favors certain traits that exist within a population. Adaptations evolve in populations. Organisms do not actively or willingly evolve. 2. Students often think of evolution as a process that improves. As the text notes, an adaptation in one context might be a handicap in another context. Reptiles are not “better” animals than fish. Neither could survive long in the other’s environment. Instead, the adaptations found in reptiles allow them to survive in a terrestrial environment, as those of fish allow them to survive in an aquatic one. Teaching Tips 1. Students may be asked to consider this question: Can individuals evolve? Sometimes such simple questions require complex answers. Might Lamarck have answered this question differently from Darwin? Module 13.2 addresses this question. Copyright © 2009 Pearson Education, Inc.