Evolution Final Exam Questions &
Answers
Define biological evolution - ANSWERSany change in the inherited traits of a population
that occurs from one generation to the next
describe the different types of evidence that support the hypothesis that whales evolved
from terrestrial vertebrates - ANSWERSlungs, placenta, live birth, drink milk produced
by mothers, three middle ear bones, hair (in developing embryo)
synapomorphies
what are the closest living terrestrial relatives of whales? how do we know this? -
ANSWERSartiodactyls and hippos; in 1990s scientists began comparing DNA and
found that whales and hippos share a more recent common ancestor with each other
than with other species of land mammals
why do mutations occur? are they always beneficial? what types of effects do they have
when they occur in virus genomes? - ANSWERSmutations occur because the cellular
machinery that replicates DNA is not perfect and occasionally makes errors
mutations may be harmful or beneficial
viruses may be less likely to be recognized by the immune system or more effective at
viral replication within the host, leads to higher reproduction, dominates the population
in subsequent generations
how can evolutionary biology help us understand and control a viral outbreak
(pandemic)? - ANSWERSevolutionary biology can help us understand the genetic
sequence of a virus to know where a virus originates, how long vaccines with provide
protection, how public health policies are best utilized, when a pandemic will end, and
how we can prevent future pandemics
natural selection - ANSWERSa mechanism that can lead to evolution, whereby
differential survival and reproduction of individuals cause some genetic types to replace
others
what is the difference between proximate and ultimate causation? provide examples of
each - ANSWERSproximate explanations focus on a mechanistic understanding of how
something happened; male sticklebacks show aggression towards red belly (sign
stimulus) of intruding male
ultimate explanations focus on historical perspectives of how something came to be;
male sticklebacks chase away others to decrease the chance eggs in his nesting
territory will be fertilized by another male
,describe the hypothetico-deductive method. explain the potential outcomes -
ANSWERSscientific inquiry proceeds by formulating a hypothesis that can be falsifiable,
using a test on observable data where the outcome is not yet known; reject hypothesis,
modify hypothesis, provisionally accept hypothesis
define the terms hypothesis, fact, and theory (as used by scientists) -
ANSWERShypothesis: informed conjecture or statement of what might be true
fact: hypothesis that has acquired so much supporting evidence that we act as if it is
true
scientific theory: a comprehensive, coherent body of interconnected statements, based
on reasoning and evidence, that explain some aspect of nature
what is the difference between how scientists use the word theory and how it is used in
everyday language? - ANSWERSa scientific theory has been proven
in everyday language, a theory refers to something that is more like a scientific
hypothesis, and has not been proven but is only an idea
carolus linnaeus - ANSWERSfather of modern taxonomy; organized living things into a
nested hierarchy of taxa
nicolas steno - ANSWERSrecognized that fossils were once living things; stratigraphy
george cuvier - ANSWERScompared elephant fossils to skeletons of living elephants
from African and India which helped establish that many fossils were remains of extinct
species
mary anning - ANSWERSdiscovered several species of extinct marine mammals
james hutton - ANSWERSrealized that rocks formed through imperceptibly slow
changes; observable processes produce small changes that accumulate over time;
earth must be old
william smith - ANSWERSnoticed that different rock layers contain distinct fossils
george buffon - ANSWERSproposed that earth had formed according to the laws of
physics over more than 70,000 years; each species had a supply of organic particles
jean-baptiste lamarck - ANSWERSbelieved traits acquired in a lifetime were passed to
offspring and that simple organisms always evolved to more complex organisms
charles darwin - ANSWERSunofficial naturalist on HMS Beagle, published Origin of the
Species, first to propose a correct mechanism for how life changed over time; descent
with modification, natural selection
alfred russel wallace - ANSWERShad similar ideas to charles darwin about evolution
and natural selection;
,charles lyell - ANSWERSearth's landscapes had been created by many small changes,
not gigantic catastrophes
what is the Great Chain of Being? why did scientists stop using it to categorize the
natural world? - ANSWERSorigin in ancient Greek philosophy; species are arranged on
a scale from lower to higher forms, fixed hierarchy, not very detailed; in the 1600s
naturalists began to develop systematic ways to classify, name, and sort species
compare and contrast Darwin's and Lamarck's hypotheses about evolution -
ANSWERSDarwin: species share traits because they evolved from a common ancestor,
some inherited traits get passed to offspring more frequently than others
Lamarck: traits acquired during a lifetime could be passed to offspring, simple
organisms always evolve into more complex organisms
what are the two major evolutionary hypotheses that Darwin proposed in The Origin of
Species? why are they now considered scientific facts? - ANSWERS1. organisms have
descended with modification from common ancestors
2. the chief cause of modification is natural selection acting on hereditary variation
new discoveries have added to proof of Darwin's theories
what role did the discovery of the fossil record play in the development of the concept of
evolution? - ANSWERSprovided evidence that life changed, fossils resemble, but are
not exactly the same as modern species, many are extinct
define uniformitarianism. how did this concept influence Darwin's thinking about
evolution? - ANSWERSearth's landscapes have been shaped by the cumulative action
of gradual processes observable today; he believed that the fossil record was made
over long periods of time
was Darwin the first naturalist to recognize that life evolved? What other concepts were
proposed to explain how life on earth changes? why do we favor Darwin's explanation -
ANSWERSno; alfred russel wallace had similar ideas, lamarck believed that traits
acquired during a lifetime could be passed on to offspring and that simple organisms
always evolved into more complex organisms; he was the first to propose a correct
mechanism for change that has been proven many times since
explain how Darwin's observations of nature (facts 1-5) lead to the inferences (1-3) he
developed regarding natural selection - ANSWERSFacts:
1. high birth rates predict exponential population growth
2. population sizes are normally stable
3. natural resources are limited
4. no two individuals are exactly the same
5. variation is heritable
Inferences:
, 1. since more individuals are born than can survive, there must be a fierce struggle for
existance
2. survival in the struggle for existence is not random and depends on heritable variation
3. over generations, heritable variation that increases survival will increase in frequency
in populations
inspired by Thomas Malthus ideas about population growth outstripping a nation's ability
to produce food
Darwin had years of research and observations
proximate explanation - ANSWERSfocus on a mechanistic understanding of how
something happened
ultimate explanation - ANSWERSfocus on historical perspectives of how something
came to be
hypothesis - ANSWERSan informed conjecture or statement of what might be true
fact - ANSWERSa hypothesis that has acquired so much supporting evidence that we
act as if it is true
scientific theory - ANSWERSa comprehensive, coherent body of interconnected
statements, based on reasoning and evidence, that explain some aspect of nature
great chain of being - ANSWERSfixed hierarchy from ancient Greece that arranged
species on a scale from lower to higher forms
taxa - ANSWERSrefer to groups of organisms that taxonomists judge to be cohesive
units
taxonomy - ANSWERSthe science of describing, naming, and classifying species
homologous trait - ANSWERSsimilar in two or more species because it is inherited from
a common ancestor
stratigraphy - ANSWERSthe study of layering in rock
paleontology - ANSWERSthe study of prehistoric life
describe how radioactive elements are used to determine the age of rocks -
ANSWERSunstable isotopes decay to a stable form over a period of time; half life is
how long it takes for half of a given sample of atoms to decay; the relative proportions of
particular isotopes in a sample are used to determine the age of rocks
how old did lord kelvin say the earth was and why? why were his estimates incorrect? -
ANSWERShe argued that the planet was less than 20 million years old but his
