APES Ch 4 Evolution

mass extinction

A catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions. Compare background extinction, mass depletion.

vertebrates

Animals that have backbones. Compare invertebrates.

invertebrates

Animals that have no backbones. Compare vertebrates.

adaptation

Any genetically controlled structural, physiological, or behavioral characteristic that helps an organism survive and reproduce under a given set of environmental conditions. It usually results from a beneficial mutation. See biological evolution, differential reproduction, mutation, natural selection.

biological evolution

Change in the genetic makeup of a population of a species in successive generations. If continued long enough, it can lead to the formation of a new species. Note that populations[[emdash]]not individuals[[emdash]]evolve. See also adaptation, differential reproduction, natural selection, theory of evolution.

genetic adaptation

Changes in the genetic makeup of organisms of a species that allow the species to reproduce and gain a competitive advantage under changed environmental conditions. See differential reproduction, evolution, mutation, natural selection.

extinction

Complete disappearance of a species from the earth. This happens when a species cannot adapt and successfully reproduce under new environmental conditions or when it evolves into one or more new species. Compare speciation. See also endangered species, mass depletion, mass extinction, threatened species.

recombinant DNA

DNA that has been altered to contain genes or portions of genes from organisms of different species.

coevolution

Evolution in which two or more species interact and exert selective pressures on each other that can lead each species to undergo various adaptations. See evolution, natural selection.

chemical evolution

Formation of the earth and its early crust and atmosphere, evolution of the biological molecules necessary for life, and evolution of systems of chemical reactions needed to produce the first living cells. These processes are believed to have occurred about 1 billion years before biological evolution. Compare biological evolution.

speciation

Formation of two species from one species because of divergent natural selection in response to changes in environmental conditions; usually takes thousands of years. Compare extinction.

subpopulation

Individuals of a species that live in a habitat patch.

genetic engineering

Insertion of an alien gene into an organism to give it a beneficial genetic trait. Compare artificial selection, natural selection.

reproductive isolation

Long-term geographic separation of members of a particular sexually reproducing species.

macroevolution

Long-term, large-scale evolutionary changes among groups of species. Compare microevolution.

background extinction

Normal extinction of various species as a result of changes in local environmental conditions. Compare mass depletion, mass extinction.

genetically modified organism (GMO)

Organism whose genetic makeup has been modified by genetic engineering.

realized niche

Parts of the fundamental niche of a species that are actually used by that species. See ecological niche, fundamental niche.

differential reproduction

Phenomenon in which individuals with adaptive genetic traits produce more living offspring than do individuals without such traits. See natural selection.

natural selection

Process by which a particular beneficial gene (or set of genes) is reproduced in succeeding generations more than other genes. The result of natural selection is a population that contains a greater proportion of organisms better adapted to certain environmental conditions. See adaptation, biological evolution, differential reproduction, mutation.

artificial selection

Process by which humans select one or more desirable genetic traits in the population of a plant or animal species and then use selective breeding to produce populations containing many individuals with the desired traits. Compare genetic engineering, natural selection.

adaptive radiation

Process in which numerous new species evolve to fill vacant and new ecological niches in changed environments, usually after a mass extinction. Typically, this takes millions of years.

mutation

Random change in DNA molecules making up genes that can alter anatomy, physiology, or behavior in offspring. See mutagen.

adaptive trait

See adaptation.

natural rate of extinction

See background extinction.

evolution

See biological evolution.

niche

See ecological niche.

gene splicing

See genetic engineering.

transgenic organisms

See genetically modified organisms (GMOs).

gene mutation

See mutation.

geographic isolation

Separation of populations of a species for long times into different areas.

fossils

Skeletons, bones, shells, body parts, leaves, seeds, or impressions of such items that provide recognizable evidence of organisms that lived long ago.

wild species

Species found in the natural environment. Compare domesticated species.

endemic species

Species that is found in only one area. Such species are especially vulnerable to extinction.

generalist species

Species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. Examples are flies, cockroaches, mice, rats, and human beings. Compare specialist species.

specialist species

Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food. Compare generalist species.

fundamental niche

The full potential range of the physical, chemical, and biological factors a species can use if there is no competition from other species. See ecological niche. Compare realized niche.

microevolution

The small genetic changes a population undergoes. Compare macroevolution.

gene pool

The sum total of all genes found in the individuals of the population of a particular species.

ecological niche

Total way of life or role of a species in an ecosystem. It includes all physical, chemical, and biological conditions a species needs to live and reproduce in an ecosystem. See fundamental niche, realized niche.

biopharming

Use of genetically engineered animals to act as biofactories for producing drugs, vaccines, antibodies, hormones, industrial chemicals such as plastics and detergents, and human body organs.

theory of evolution

Widely accepted scientific idea that all life forms developed from earlier life forms. Although this theory conflicts with the creation stories of many religions, it is the way biologists explain how life has changed over the past 3.6[[endash]]3.8 billion years and why it is so diverse today.

mass depletion

Widespread, often global period during which extinction rates are higher than normal but not high enough to classify as a mass extinction. Compare background extinction, mass extinction.

domesticated species

Wild species tamed or genetically altered by crossbreeding for use by humans for food (cattle, sheep, and food crops), pets (dogs and cats), or enjoyment (animals in zoos and plants in gardens). Compare wild species.

An organism's niche is analogous to its a. address. b. way of life. c. food source. d. trash dump. e. All of these answers.

b. way of life.

Which of the following best describe biologists' current hypothesis about the production of the earth's atmospheric oxygen? a. Photosynthesis by terrestrial plants produced atmospheric oxygen. b. The breakdown of iron ore deposits produced atmospheric oxygen. c. Photosynthesis by cyanobacteria produced atmospheric oxygen. d. Chemosynthesis by terrestrial plants produced atmospheric oxygen. e. Chemosynthesis by aquatic plants produced atmospheric oxygen.

c. Photosynthesis by cyanobacteria produced atmospheric oxygen.

Gould's view of macroevolution as long periods of relatively little change interrupted by short periods of relatively rapid change is best described as a. dynamic equilibrium. b. a steady state hypothesis. c. a punctuated equilibrium hypothesis. d. a gradualist model of evolution. e. natural selection

c. a punctuated equilibrium hypothesis.

Which of the following is not considered evidence for evolution? a. the fossil record b. chemical analysis c. DNA analysis d. cores drilled out of buried ice e. All of the above are correct

e. All of the above are correct

Geographic isolation may result from a. a volcanic eruption. b. an earthquake. c. a mountain range. d. a river e. All of these answers.

e. All of these answers.

The most likely sequence for the biological evolution of life is a. aerobic prokaryotes—photosynthetic prokaryotes—anaerobic prokaryotes—eukaryotes—multicellular organisms. b. photosynthetic prokaryotes—anaerobic prokaryotes—aerobic prokaryotes—eukaryotes—multicellular organisms. c. anaerobic prokaryotes—photosynthetic prokaryotes—aerobic prokaryotes—eukaryotes—multicellular organisms. d. eukaryotes—anaerobic prokaryotes—photosynthetic prokaryotes—aerobic prokaryotes—multicellular organisms. e. aerobic prokaryotes—eukaryotes—anaerobic prokaryotes photosynthetic prokaryotes—multicellular organisms.

c. anaerobic prokaryotes—photosynthetic prokaryotes—aerobic prokaryotes—eukaryotes—multicellular organisms.

Which of the following statements is false? a. Genetic diversity helps prevent a species from becoming extinct. b. The phenomenon in which animals with favorable adaptation reproduce more rapidly is called differential reproduction. c. Geographic isolation is a common mechanism contributing to speciation. d. By definition, the fittest animals are the largest and strongest animals. e. Biologists estimate that 99% of all the species that have ever existed are now extinct.

d. By definition, the fittest animals are the largest and strongest animals.

Patterns of speciation and extinction are least likely to be affected by a. climatic changes. b. continental drift. c. meteorites crashing into the earth. d. changes in the weather. e. human activity

d. changes in the weather.

A change in the genetic composition of a population over successive generations is called a. emigration. b. mutation. c. natural selection. d. evolution. e. genetic drift.

d. evolution.

You are a fossil hunter. Which of the following are you least likely to find in a fossil? a. bone b. leaves c. teeth d. muscle e. shells

d. muscle