Darwin’s Theory of Evolution Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

WRITE A DEFINITION: EVOLUTION: THEORY: FOSSIL: change over time; the process by which modern organisms have descended from ancient organisms a well-supported testable explanation of phenomena that have occurred in the natural world the preserved remains of ancient organisms

evolution fossil theory The _______ that Darwin found caused him to ask questions that led to his proposal of the theory of _________. _______ provide evidence to support the theory of _________. ________ is a ______; a testable explanation of naturally- occurring phenomena The _____ record provides for some of the evidence that supports the ______ of evolution Evolution theory fossils evolution Fossils evolution fossil theory

What scientific explanation can account for the diversity of life? ANSWER: A collection of ______________, __________, and ___________ known as ________________________ Scientific facts observations hypotheses EVOLUTIONARY THEORY

The person who contributed the most to our understanding of evolution was ______________________ In 1831, at age 22, he joined the crew of the _______________ as a naturalist for a ________ voyage around the world. Charles Darwin H.M.S. Beagle Image from: Biology by Miller and Levine; Prentice Hall Publishing© year

After his voyage, Darwin spent a great deal of time thinking about his findings. He began to wonder if animals living on different islands had once been members of the ____________ that had developed _________ characteristics after becoming _______ from one another in different habitats. same species different isolated Biology by Miller and Levine; Prentice Hall Publishing©2006

Ideas that shaped Darwin’s thinking: In 1785 ______________ proposes that the ______________ by _________________ occurring over __________ periods of time, and is _______________ old. very long James Hutton Earth was shaped geological forces millions of years

Ideas that shaped Darwin’s thinking: In 1833 ___________ explains that the geological processes still ___________ have shaped Earth’s features over ________________ Charles Lyell occurring now long periods of time

Ideas that shaped Darwin’s thinking: Theory of Pangaea …and continental drift

Living things must compete for food, shelter, space, mates competition REMEMBER !

Ideas that shaped Darwin’s thinking: _____________________ He observed that babies were being born faster than people were dying. He reasoned that if the human population continued to grow, sooner or later there would be _______________________ Thomas Malthus (1798) insufficient space & food

Ideas that shaped Darwin’s thinking: ___________________________ was one of first scientists to recognize living things _______________ and that all species were ________ from other species. Lamarck published his hypothesis of ________________________ the year Darwin was born. changed over time Jean-Baptiste Lamarck (1809) descended Inheritance of Acquired traits

The male fiddler crab uses its front claw to attract mates and ward off predators. Through repeated use, the front claw becomes larger. The fiddler passes on this acquired characteristic to its offspring

What’s wrong with Lamarck’s hypothesis? Lamarck didn’t know about genes and how traits are _______. If you lifted weights your whole young adult life, and then you had children, would your kids be more muscular? inherited NO! Acquired traits may help the individual organism, but they won’t be passed on to offspring.

What’s right with Lamarck’s hypothesis? Lamarck was first to develop a scientific hypothesis about _______ and recognize that organisms are ________________________ evolution adapted to their environments

a.The earth is really old, and slowly changes b.Living things pass changes on to their offspring, leading to species changes c.Sooner or later growing populations run out of resources d.Living things change slowly over time because of competition for resources, and pass those changes on to their offspring Hutton Lyell Malthus Lamarck Match the letter of the idea with the man or men who proposed it:

a.The earth is really old, and slowly changes b.Living things pass changes on to their offspring, leading to species changes c.Sooner or later growing populations run out of resources d.Living things change slowly over time because of competition for resources, and pass those changes on to their offspring Hutton Lyell Malthus Lamarck a. c. b. d.

In 1859 ____________________ presented _______ and proposed a ________ for evolution that Darwin called __________________ On the Origin of Species evidence mechanism NATURAL SELECTION

EVIDENCE OF EVOLUTION: 1.________________ 2.________________ 3. _______________ 4. _______________ 5. _______________ 6. _______________ 7. _______________ Fossil record Geographic Distribution Homologous structures Embryology DNA See Natural selection happen Artificial selection

ARTIFICIAL SELECTION In artificial selection, nature provides the variation through mutation and sexual reproduction and humans select those traits that they find useful EX: We have selected for and bred cows to produce more milk, turkeys with more breast meat, etc.

Breeds of Dogs Chihuahua – bred from Techichi of Mexico by Mayans, had religious significance Saint Bernard – bred by monks around 1050 A.D. to rescue travelers of mountain passes in the Swiss Alps between Italy and Switzerland Irish Wolfhound – bred in Ireland to hunt wolves and elk Dachshund – bred in Germany as early as the 15 th century to hunt badgers SLIDE FROM: BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

How Do We Know Evolution Happens? 2. The Fossil Record – ______ are the _______ _________________ found in layers of rock in the Earth. Fossils of ancient organisms remains

How Do We Know Evolution Happens? The layers of rock tell the history of the _____, while the _____ found within the rock tell a history of ___. The fossils are thought to be the ________ as the rock they are found in. Earthfossils life same age

If Darwin’s theory is correct you would expect to find ____________ yet _______________ living in a _________ region as they spread into nearby habitats and evolve. different species closely related geographic That’s EXACTLY what we do see! 3. Geographic distribution

REMEMBER THE GALAPAGOS TORTOISES Image from: BIOLOGY by Miller and Levine; Prentice Hall Publisher©2006 Little vegetation Long necks Lots of vegetation Short necks Intermediate vegetation Intermediate necks Tortoises adapted to different habitats as they spread from the mainland to the different islands. = DIVERGENT EVOLUTION = ADAPTIVE RADIATION

GALAPAGOS FINCHES The _____ of Galapagos finches have ______ to eating a _____ of _____. beaks adapted varietyfoods

Whales and sharks have a _____ body design even though they are very _______ organisms (one is a fish; the other, a mammal) because they have _________________ to living in a _____ environment. = CONVERGENT EVOLUTION similar different independently adapted similar

Whales are closely related to wolves, but don’t look or act much like them = divergent evolution Whales are distantly related to sharks, but look and act more like them = convergent evolution Conclusion: The pressure of the environment drives evolution

4. _____________________ Image from: HOMOLOGOUS Structures

4. Homologous Body Structures – Structures, like the limbs of vertebrates, look very _______, but are made from the __________, because they are made from the same clump of _____________ cells in the _______. same bones embryo undifferentiated Image from: different

4. Homologous Body Structures – Some _______________________ are _______ and have no useful function even though they are still present, like ________in whales and boa constrictors, or a ____ and ________________in humans. homologous body structures vestigial hipbones tail cecum (appendix)

5. _____________________ ________ of many animals with back- bones are very similar. Similarities in Embryology Embryos Image from:

It is clear that the same groups of _____________ cells develop in the same order to produce the same tissues and organs of all vertebrates, suggesting that they all _______ from a _______________. undifferentiated evolved common ancestor Image from:

Image from: BIOLOGY AP EDITION by Campbell and Reece; Prentice Hall Publishing© _______________ Similarities in ____ and ________ sequences suggest relatedness Similarities in DNA PROTEIN DNA

Similar _________ suggest an ___________________. Human: Chimpanzee: Middle School Life Science, published by Kendall/Hunt. Human- 46 chromosomesChimpanzee- 48 chromosomes karyotypes evolutionary relationship

Fish, amphibians, reptiles, and most mammals can make their own _________, but humans need to eat fresh fruit or they end up with ________. VITAMIN C SCURVY

Human DNA contains the gene that codes for the enzyme to make vitamin C, but it is ________________. Guess what other group of organisms lack the ability to make their own Vitamin C? NONFUNCTIONAL PRIMATES… which includes chimpanzees, orangutans, gorillas, and other apes.

Humans have many other nonfunctional vestigial genes called ________________. EX: Humans have more than 99 different odor receptor genes, but more than 70% of them are ___________. PSEUDOGENES nonfunctional

7.____________________________ EX: Changes in disease-causing microbes that produce new organisms and __________. _______ ___ __________________________ Can see Natural selection happen Bird flu Antibiotic-resistant tuberculosis HIV new diseases

Go to Section: Concept Map Section 15-3 includes Evidence of Evolution Physical remains of organisms Common ancestral species Similar genes which is composed ofwhich indicateswhich implies The fossil record Geographic distribution of living species Homologous body structures Similarities in early development

The preceding presentation adapted from the following: