The technique called radiometric dating is based on
the steady, clocklike decay of certain radioactive isotopes over time.
The Mesozoic era is often called the age of reptiles. Which of the following also occurred during this era?
the appearance of the first mammals and flowering plants on land
Under the biological species concept, a species is a group of organisms that
have the potential to interbreed in nature and produce fertile offspring.
Genetic differences between populations tend to be reduced by
One of the key contributions of the punctuated equilibrium model is that it helps explain
why transitional fossils tend to be rare and certain common fossil species remain unchanged for long time spans.
The ultimate source of all new alleles is
Which of the following options lists taxonomic categories in the correct order from most specific to most general?
genus, family, order, class, phylum
Who developed a theory of evolution almost identical to Darwin’s?
A population of 1,000 birds exists on a small Pacific island. Some of the birds are yellow, a characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. Only 10 remain, and those birds all have yellow feathers. T/F. The hurricane has caused a population bottleneck and a loss of genetic diversity.
A group of ants escaped from a picnic basket carried to the top of a mountain and thrived in this area where there were no other ants. Many years later descendants of these ants crawled into a picnic basket on the mountain and traveled back to the valley from which their ancestors had come. Which of these observations would cause you to conclude that the ants on top of the mountain had become a different species from those in the valley?
The mountain ants could not mate with the valley ants.
Which of the following would a biologist describe as microevolution?
a change in the gene pool of a population from one generation to the next
Some butterflies can ingest toxic chemicals from the milkweed plants they feed on and then can store those chemicals in their body. Because toxins stored in the butterflies are toxic to birds, the birds avoid eating the butterflies. Which of the following is the best explanation for this situation?
Any butterfly allele that allowed milkweed toxin storage would be likely to persist because butterflies that had it were more likely to survive.
If all of Earth’s history were compressed into an hour, humans would first appear less than
1 second ago.
In the three-domain system, the eukaryotes are represented
only within the domain Eukarya.
Scientists believe that a major factor promoting the adaptive radiation of mammals was probably
the mass extinction of most dinosaurs, an event that opened up new ecological opportunities.
Which of the following options lists major events in the history of life on Earth in the proper order, from earliest to most recent?
first prokaryotes, photosynthesis, first eukaryotes, colonization of land by plants and fungi
Which of the following disciplines has found evidence for evolution based on the native distributions (locations) of living species?
Darwin found that many of the species on the Galápagos islands
resembled species on the nearest mainland.
Over a span of several thousand years, a number of species show adaptations to climate change: Drier, warmer conditions select for succulent vegetation and deep taproots in plants, burrowing in mammals and amphibians, and other similar adaptive changes. What will happen if the climate shifts in the opposite direction and becomes progressively wetter and cooler?
Different adaptive trends will probably be favored in the new climatic environment.