An Intro to Evolution

Describe two examples in which agreement among different lines of evidence provides evidence for evolution.

(a) Fossils (b) Evidence of molecular clocks, radiometric dating

During the formulation of his theory of evolution by natural selection, Darwin brought together ideas and results from several disciplines. Match the person with the phrase that describes his work. a. Lyell b. Wallace c. Lamarck d. Cuvier -Evidence of extinction of species -One form of organism can evolve into another -Natural selection as a mechanism underlying evolution -Geological forces observable today caused changes in Earth

-Evidence of extinction of species (d) -One form of organism can evolve into another (c) -Natural selection as a mechanism underlying evolution (b) -Geological forces observable today caused changes in Earth (a)

Vestigal character

A structure in an organism whose original function has been lost during the course of evolution

Radiometric dating

A technique for determining the age of objects by measuring the decay of the radioactive elements they contain

Alfre Russel Wallace

Came to the same conclusion about evolution as Charles Darwin. Wallace wrote to Darwin in regards to his findings and as soon as he did Darwin published his information.

What is one observation that Darwin made in the Galapagos that influenced his thinking about evolution, and why was it important? Would he have been as likely to formulate his theory had he not had the opportunity to sail on the Beagle? Why or why not?

Darwin brought back many birds that he thought were the blackbirds, wrens, and warbles he was familiar with in Britain, but he found they were in fact all species of finches. He perceived this as common descent with modification.

George Cuvier

Extinction and Catastrophism -Examined fossil rocks and provided evidence on extinction of species on Earth -Brought about that there had been a series of catastrophes that had wiped out species in a given area.

Catastrophes

Flood, ice age, tsunami, earthquake, etc. Natural disasters

Common descent with modification (First evolutionary principle)

Holds that particular groups or species of living things can undergo modifications in successive generations. This can result in the formation of a new species. One species separating into two and so on.

What is homology and why does it provide evidence for evolution?

Homology describes structures in different species that are similar due to common ancestry. It provides evidence because it is consistent with the idea of common descent with modification.

Jean-Baptiste de Lamarck

Inheritance of Acquired Characteristics -He believed an animal would acquire enough changes that one species would diverge into two -Species changed/adapted to their environment (Giraffe example) Although false for the most part, he did understand that organisms could evolve and share an ancestral lineage.

Natural selection (Second evolutionary principle)

Process through which traits that confer a reproductive advantage to individual organisms, grow more common in populations of organisms over successive generations.

Morphology

Study of the physical forms that organisms take -Seen in the similar forelimb structures found in very diverse groups of mammals. (Whale, cate, bat, gorilla)

Modern Synthesis

The convergence of several lines of biological research into a unified evolutionary theory

Charles Lyell

Uniformitarianism Geologist -Earth had not been put into final formation at a moment of creation, but rather was steadily undergoing change.

Which of the following are central ideas in the theory of evolution by natural selection? (List all that apply.) a. Organisms vary in traits that affect their reproduction. b. Descent with modification occurs over generations. c. Evolution has a goal d. Traits that confer a reproductive advantage will become more common in populations over time. e. Traits that are acquired during the life of an individual contribute to evolution

a, b, d

Important implications of the theory of evolution by natural selection include (select all that apply): a. all organisms, including humans, are descended from a common ancestor. b. the biological world is constantly evolving c. nature designs things intentionally d. traits found in organisms are the outcomes of a goal-less process e. humans occupy one ordinary branch on an enormous tree of life

a, b, d, e

Which of the following observations provide evidence for evolution? (List all that apply) a. Monkey and trilobite fossils are never found in the same fossil beds. b. Athletic training can produce an increase in muscle mass c. DNA sequences of genes shared by various species vary in accordance with predictions about how closely related those species are. d. The genetic code is nearly universal. e. Species whose adult forms look very different may have similar features in embryonic life.

a, c, d, e

John Endler performed an experiment involving guppies in which he demonstrated evolution driven by natural selection that world through a predator-prey relationship. Which of the following are true statements about the results of his experiments? (Select all that apply) a. Males with longer tails and brighter coloration were more frequently eaten by predator fish. b. Females preferred to mate with dull colored males. c. When males were put in a predator free environment, brighter coloration and larger tails evolved in them. d. In the predator-free environment, the average brightness of females increased. e. When predators were reintroduced, duller coloration and smaller tails evolved in the males.

a, c, e

In science, a theory is: a. an untested hypothesis b. a general set of principles, supported by evidence, that explains some aspect of the natural world. c. speculation about the natural world, based on general knowledge of a field. d. an observation e. the first idea proposed to explain some aspect of the natural world.

b

Some of the following structures are homologous with each other. Which ones are they, and which two do not belong to this group? a. whale flipper b. insect leg c. bat wing d. cat forelimb e. octopus tentacles

b, e (are not) a, c, d (are homologous)

Discoveries in the field of ________ provide key evidence needed for natural selection to be widely accepted as the mechanism of evolution (select one). a. radiometric dating b. fossils c. genetics d. DNA sequencing e. medicine

c