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Flashcards in Key Terms for Exam 1 Deck (43):
1

Any change in the inherited traits of a population that occurs from one generation to the next (over a period longer than the lifetime of an individual in the population)

Biological evolution

2

A process by which populations of organisms change over time

Evolution

3

A chain of ancestors and their descendants.
May be the successive generations of organisms in a single population, the members of an entire species during an interval of geological time, or a group of related species descending from a common ancestor

Lineage

4

A mechanism that can lead to evolution, whereby differential survival or reproduction of individuals causes some genetic types to replace (outcompete) others

Natural selection

5

The independent origin of similar traits in separate lineages

Convergent evolution

6

Characteristics are similar in two or more species because they are inherited from a common ancestor

Homologous

7

A derived form of a trait that is shared by a group of related species (i.e., one that evolved in the immediate common ancestor of the group and was inherited by all its descendants).

Synapomorphy

8

A visual representation of the evolutionary history of populations, genes or species

Phylogeny

9

Any change to the genomic sequence of an organism

Mutation

10

Occurs when genetic material from different strains get mixed into new combinations within a single individual

Viral reassortment

11

Evolution arising from random changes in the genetic composition of a population from one generation to the next

Genetic drift

12

A protein on the surface of the influenza virus that latches it to a host cell

Hemagglutinin

13

Measurable aspects of organisms, such as morphology (structure), physiology, and behavior. Genes interact with other genes and with the environment

Phenotypes

14

A group of organisms that a taxonomist judges to be a taxonomic unit, such as a species or order

Taxon (taxa)

15

The science of describing, naming, and classifying species of living or fossil organisms

Taxonomy

16

The study of layering in rock

Stratigraphy

17

The study of prehistoric life

Paleontology

18

The permanent loss of a population or species, arising with the death or failure to breed of the last individual

Extinction

19

The idea that the natural laws observable around us now are also responsible for events in the past.

Uniformitarianism

20

Traits are similar because they are inherited from a common ancestor

Homologous

21

Traits are similar because they have converged on a shared form. Not derived from a common ancestor

Analogous

22

A mechanism that can lead to evolution, whereby differential reproduction of individuals causes some genetic types to replace (outcompete) others

Natural selection

23

Inherited aspects of an individual that allow it to outcompete other members of a population that lack the trait (or that have slightly different version of the trait).

Adaptations

24

Arises when individuals of one sex (usually males) compete with each other over access to individuals of the other sex. It can lead to the evolution of traits like showy ornaments or weapons that improve an individual's chances of mating

Sexual selection

25

A change in the frequency of traits or genetic variants that arises across generations due to random events. Most pronounced in small populations

Genetic drift

26

Terminal ends of an evolutionary tree, representing species, molecules, or populations being compared

Tips

27

Lineages evolving through time between successive speciation events

Branches

28

A point in a phylogeny where a lineage splits (a speciation event)

Node

29

Nodes within a phylogeny representing ancestral populations or species

Internal nodes

30

An organism and all of its descendants

Clade

31

A term used to describe a group of organisms that form a clade

Monophyletic

32

Heritable aspects of organisms that can be compared across taxa

Characters

33

Phylogenetic methods that construct trees by grouping taxa into nested hierarchies (clades) according to their shared derived characters (synapomorphies)

Cladistics

34

Character state similarity not due to shared descent (ex. produced by convergent evolution or evolutionary reversal)

Homoplasy

35

The reversion of a derived character state to its ancestral state

Evolutionary reversal

36

A trait that originates performing one function, and which is later co-opted for a new function

Exaptation

37

Members of the hominin genus Australopithecus

Australopithecines

38

Similar to natural selection, except that it results from human activity. When breeders nonrandomly choose individuals with economically favorable traits to use as breeding stock, they impose strong _____ on those traits.

Artificial selection

39

The transfer of alleles from one population to another. Occurs when organisms or their gametes move from one location to another

Gene flow

40

Structures constructed by organisms that can influence their performance or success. Although they are not part of the organism itself, their properties nevertheless reflect the genotype of each individual. Animal examples include the nests constructed by birds and the galls of flies.

Extended phenotypes

41

An antipredator strategy used by a potential prey item to signal danger or a lack of palatability. Ex. warning coloration

Aposematism

42

The physical proximity of alleles at different loci. Genetic loci that are physically close to one another on the same chromosome are less likely to be separated by recombination during meiosis, and are thus said to be....

Genetic linkage (genetically linked)

43

Strong selection can "sweep" a favorable allele to fixation within a population so fast that there is little opportunity for recombination.

Selective sweep