| Fossils are predominantly found in ____ | sedimentary rocks |
| Fossilized wood and bone fragments can be accurately aged using ____ | Carbon-14 |
| The fourteen species of finches native to the Galápagos Islands ____, and therefore illustrate adaptive radiation. | evolved from a single common ancestor |
| The potential seventh mass extinction refers to ____ | the rapid loss of biodiversity due to human degradation of the environment |
| Female fireflies identify males by their flashing patterns, which are often so complicated that signals sent by one species cannot be understood by another species. This reproductive isolating mechanism is called ____ | behavioral isolation |
| To distinguish two organisms using the morphological species concept, a scientist would ____ | look at the appearance of two organisms |
| Analysis of human chromosome 2 reveals that it was produced by the ____ that are still present in our closest ancestral ape relatives. | fusion of two smaller chromosomes |
| Which combination is an example of prezygotic mechanisms of isolation? | mechanical and temporal isolation |
| Over time, the carbon isotope 14C decays into ____ | 14N |
| The phylogenetic species concept looks at ____ | morphology and genetic data |
| Postzygotic isolating mechanisms occur when the offspring ____ | inherit different developmental instructions from each parent |
| To answer questions about the genetic changes underlying speciation, scientists are now isolating and sequencing ____ | speciation genes |
| A zebroid is the sterile hybrid offspring of a horse and a zebra. This is an example of ____ | hybrid sterility |
| allopolyploidy | two closely related species hybridize and form polyploid offspring |
| phylogenetic species concept | species comprise populations that share a recent evolutionary history on the Tree of Life |
| subspecies | local variants of a species that exhibit dramatic, easily recognized phenotypic differences |
| biological species concept | species are members of natural populations that interbreed and produce fertile offspring |
| autopolyploidy | chromosome duplications within a single species give rise to polyploid individuals |
| morphological species concept | all individuals of a species share measurable traits that distinguish them other species, |
| species cluster | a group of closely related species recently descended from a common ancestor |
| Allopatric speciation typically occurs in two stages. The first stage is ____ of two populations and the second stage is ____ | geographic separation; reproductive isolation |
| The biological species concept emphasizes the ability of individuals to ____ | interbreed and produce fertile offspring |
| The radioactive decay of carbon-14 can be used to determine ____ | absolute dating |
| The marsupial mammals of Australia and the placental mammals of North America include many pairs of morphologically convergent species. | True |
| Speciation that takes place when a physical barrier subdivides a large population is called ____ speciation. | allopatric |
| A small population isolated at the edge of a species’ geographic distribution may experience ____ and genetic drift, which may lead to the evolution of distinctive traits by ____ | a founder effect; natural selection |
| Abrupt genetic changes that quickly lead to the reproductive isolation of a group of individuals will likely lead to ____ | sympatric speciation |
| On the Hawaiian Islands, speciation in Drosophila occurred when a small group of males and females colonized a new island, where they faced environmental selection pressures. In addition, sexual dimorphism – and therefore, sexual selection – maintained reproductive isolation from other populations on the new island. These populations, although closely related, remained ecologically different. These events are examples of ____ | a founder effect, genetic drift, and adaptive radiation |
| A paleontologist estimates that when a particular rock formed, it contained 12 mg of the radioactive isotope potassium-40, which has a half-life of 1.25 billion years. The rock now contains 3 mg of the isotope. About how old is the rock? | 2.5 billion years |
| Which group of animals are living representatives of the theropods, a lineage of bipedal predatory dinosaurs? | birds |
| ecological isolation | species live in different habitats |
| temporal isolation | species breed at different times |
| behavioral isolation | species cannot communicate |
| mechanical isolation | species cannot physically mate |
| gametic isolation | species have nonmatching receptors on gametes |
| hybrid inviability | hybrid offspring do not complete development |
| hybrid sterility | hybrid offspring cannot produce gametes |
| hybrid breakdown | hybrid offspring have reduced survival or fertility |
