exam 4 Flashcards
a requirement of cladistics is that a grouping must include _____
a common ancestor and all its descendants
the reduction in genomic variability that occurs when a small group of individuals becomes separated from a larger population
founder effect
an extreme example of genetic drift that happens when the size of a population is severely reduced
bottleneck effect
the change in frequency of an existing gene variant in the population due to random chance
genetic drift
any movement of individuals and/or the genetic material they carry from one population to another
gene flow
an individual weed that exhibits resistance to an herbicide _____
inherited the gene that made it resistant
by what means did darwin propose species evolved over time
natural selection
before the publication of charles darwin’s On the Origin of Species, what was the prevailing public consensus regarding species evolution
that species were permanent and unchanging
comparing DNA sequences to find evidence of shared evolutionary history is called
bioinformatics
comparing the body structures of organisms to find evidence of a shared evolutionary history is called
comparative anatomy
change in gene frequency in a population is best defined as
evolution
if two organisms of different species share more similar DNA sequences with each other than with other species then we can conclude that
these two species are very closely related
individuals with variations that make them best suited to their environment are, on average, more likely to _____
survive and reproduce
natural selection acts on _____ and _____ evolve
individuals; populations
what category of biological classification is the most narrow
genus
some of the branches of a phylogenetic tree do not extend to the end, what do these lines represent
extinct species
the oldest fossils are typically found in the _____ sediments
lower
the rapid diversification of species seen in the fossil record followed by long periods of stasis is part of the _____ model of evolution
punctuated equilibrium
the slow drifting of sections of the earths crust, sometimes separating, other times colliding, is known as
plate tectonics
what defines a geological time period known as an era
the distinct life forms that were present
how many offspring an individual produces is considered _____
fitness
what events can lead to offspring having a unique arrangement of their parents genes
crossing over and independent assortment
what field of science has as its goal to classify all living things into hierarchical system of relatedness that runs from most broad to most narrow
taxonomy
the process of determining the age of a fossil from radioactive isotopes is
radiometric dating
what is the name for the study of the geographic distribution of species
biogeography
what is the smallest unit that can evolve
the population
what is the original source of variation that natural selection acts upon
mutations
the failure of one species sperm to fertilize the egg of a different species
gametic incompatibility
when did life first appear on the planet
3.5 billion years ago
what biological classification grouping includes the greatest number of species
domain
what grouping follows Order in the classification hierarchy
family
what grouping includes all protists
domain eukarya
mineralized bones, animals frozen in ice or preserved in amber, and footprints or other impressions preserved in stone are considered
fossils
changes in genes within a population over time is
microevolution
natural selection, genetic drift, and founder effect can all cause
evolution
what can lead to allopatric speciation
habitat isolation
what process of evolution does not change the total number of species
nonbranching evolution
