CHAPTER 18

Homoplasy

A similar (analogous) structure or molecular sequence that has evolved independently in two species.

Both Darwin and ________ arrived at the conclusion that evolution occurs by natural selection.

Alfred Russel Wallace

Fieldwork conducted by _______________ was instrumental in establishing that natural selection is the actual mechanism of evolution.

Charles Darwin

The Modern Synthesis incorporates the ideas and observations of _____________ and _________________ .

Darwin / Mendel

Darwin's theory of evolution used data he collected on the similarities and differences among organisms he observed in the ________________, a chain of islands west of mainland Ecuador.

Galapagos Islands

Charles Darwin served as a naturalist on the ________________ ship.

H.M.S. Beagle

Comparative anatomy of related species demonstrates similarities in their structures. _______________ features are those derived from the same structure in a common ancestor and the condition is known as ____________ .

Homologous / homology

________ are the remains of organisms that existed over a relatively short geological time period and that died and were preserved as fossils in large numbers. They are used to identify specific sedimentary layers and to arrange layers in chronological order.

Index fossils

________ proposed the hypothesis that traits acquired during an organism's lifetime could be passed along to their offspring.

Jean Baptiste de Lamarck Lamarck

________ was the first to propose that organisms change over time as a result of natural phenomenon.

Jean Baptiste de Lamarck Lamarck

The first comprehensive hypothesis of evolution, which proposed that organisms change as a result of natural phenomenon and not divine intervention, was proposed by:

Lamarck

________ was probably the first to recognize that fossils are the remains of extinct organisms.

Leonardo da Vinci

The person who supplied evidence that the earth was old enough to provide adequate time for evolution and the appearance of new species to have occurred was:

Lyell

The person(s) who suggested that populations increase geometrically and that their numbers must eventually be checked was:

Malthus

In 1859, Darwin published his monumental book, ________.

On the Origin of Species

Biogeography

Study of past and present distribution of organisms

________ made the important mathematical observation that populations increase in size geometrically until checked by factors in the environment.

Thomas Malthus

The two people who proposed that the mechanism for the evolution of organisms is by natural selection were:

Wallace / Darwin

Evolution is the ________.

accumulation of genetic changes within populations over time

An evolutionary modification that improves the chances of survival of oak trees in North America would be considered to be an ________.

adaptation

Darwin's theory of evolution states accumulation of ______________ in a population can lead to new species

adaptations

Darwin's theory of evolution states better ___________ individuals are more likely to survive

adapted

The humerus in a bird and human are probably derived from a common ________.

ancestor

When horse breeders mate female and male horses to produce the strongest and fastest racing horses, they are using ________ to produce these traits.

artificial selection

The distribution of plants and animals supports evolution. The study of the past and present geographic distribution of plants and animals is called ________.

biogeography

Darwin's thoughts about evolution were influenced by the __________ of domestic animals

breeding

A species will exhibit ___________ behaviors

common

If Darwin had known about and employed current biochemical and molecular biology techniques, it would have resulted in: ________________ of his theories

confirmation

The fossil record is ________________ with Darwin's theory of natural selection

consistent

In 1915 Alfred Wegener proposed that a single land mass called Pangaea had broken apart in a process known as _______.

continental drift

There are times when organisms living in similar environments but not in the same geographical region evolve similar adaptations. The independent evolution of similar structures is referred to as ________.

convergent evolution

The formation of fossils is most likely to occur under conditions that favor rapid covering of a dead organism by sediment and preventing body _______________ .

decay

The concept of ___________ is based upon past and current evidence that organisms living today evolved from earlier organisms, and it links all fields of the life sciences into a unified body of knowledge.

evolution

The fossil record supports contemporary theories of _______________

evolution

The fossil record sometimes appears _____________

fragmentary

Molecular comparisons among organisms provide evidence for evolution. The molecular evidence for evolution includes the universal __________________ and the presence of ________________.

genetic code / pseudogenes

Darwin's thoughts about evolution were influenced by the work of ____________

geologists

Each radioisotope has its own rate of decay and its ____________ does not change regardless of the environmental conditions.

half-life

The fossil record provides strong evidence for evolution. The fossil record demonstrates that life ________.

has evolved through time

The Modern Synthesis strengthens scientific understanding of evolution by uses genetics to explain the source of ______________variation that is essential to natural selection

hereditary

Structures of different organisms that have a similar form due to a common evolutionary origin are:

homologous

The humerus in a bird and human are ho_________ but not ho___________

homologous / homoplastic

The wings of a butterfly and a bat are: __________________ but not homologous

homoplastic

Non-homologous features that have similar function but evolved independently are called ________.

homoplastic features

Aardvarks, anteaters, and pangolins are only distantly related, but are similar in structure and form as a result of:

homoplasy convergent evolution

The genetic changes that bring about evolution do not occur in ____________, but rather in _______________.

individual organisms / populations

A species is a group of __________________ organisms

interbreeding

The fossil record includes evidence from both ___________ and ______________

land and water

The fossil record includes evidence of an animal's ______________, such as how they walked

life

Evolution typically occurs over ________.

long time spans many generations

Evolution of major taxonomic groups is called ________________ and evolution of populations is called _________________ .

macroevolution / microevolution

The synthetic theory of evolution explains variation in terms of ________ , which are inheritable and therefore potential explanations for how variations in traits are passed from one generation to another.

mutations

Charles Darwin proposed that evolution could be explained by the differential reproductive success of organisms that resulted from their naturally occurring variation. Darwin called this process:

natural selection

________________________ works because each species produces more offspring than will survive to maturity, genetic variation exists among the offspring, organisms compete for resources, and individuals with the most favorable characteristics are most likely to survive and reproduce.

natural selection

In _____ the selecting agent is the environment, whereas in _____ the selecting agent is humans.

natural selection; artificial selection

The genetic code provides evidence that all ___________ arose from a common ancestor

organisms

Darwin proposed that evolution occurs by natural selection. Darwin's mechanism of natural selection consists of five premises based on observations about the natural world. In summary, these are:

overproduction genetic variation limits on population growth struggle for existence differential reproductive success

Darwin's thoughts about evolution were influenced by the many varieties of ______________ of the same species

plants

A species may be comprised of multiple ______________________

populations

Evolution is the accumulation of genetic changes within _____ over time.

populations

Fossils can be dated by determining the ratio of _______________ in a rock or fossil sample.

radioisotopes

Of the many places that organisms live, the bodies of those organisms living in ________ are least likely to become fossilized, because those are moist, humid environments in which decomposition occurs rapidly.

rainforests

Aristotle was one of the first individuals to group and arrange organisms. To do this he used what he called a ________.

scale of nature

The fossil record usually occurs in _______________ rock

sedimentary

Darwin's theory of evolution states organisms evolve by a process of natural _______________.

selection

A group of organisms that are capable of interbreeding are classified as a ________.

species

Over time, changes occur in the gene pools of geographically separated populations that may lead to the evolution of new ___________.

species

A species is a group of organisms with similar _________________

structures

A subsequent modification of Darwin's theory, the ____________ theory of evolution, explains Darwin's observation of variation among offspring in terms of mutation and recombination.

synthetic

The fossil record demonstrates that life evolved through ____________

time

The genetic code specifies a _______________ of nucleotides in mRNA

triplet

The concept of evolution is the cornerstone of biology because it links all fields of the life sciences into a _____________ body of knowledge

unified

The genetic code is virtually _____________

universal

The occasional presence of "remnant organs" in organisms is to be expected as species evolve and adapt to different modes of life. Such organs or parts of organs, called ________, are degenerate and have no apparent function, or have been reduced in their function.

vestigial organs vestigial structures