5 Mechanisms
This nonrandom force involves individuals carrying new alleles into existing populations, thus altering allele frequencies.
The strongest evidence of evolution.
What is molecular sequence data?
The only living species of human.
What are Homosapiens?
A change in the gene pool in a population over time.
What is evolution?
The approximate age of the Earth.
What is 4.6 billion years?
The single force of evolution that, while random, is the only way for a completely new allele to enter the gene pool.
What are mutations?
The movement of continents across the Earth's surface due to the shifting of tectonic plates.
What is continental drift?
The general group of animals that humans fall in, their characteristics are: five-fingered grasping hands and feet with nails, binocular vision, and have large brains.
What are primates?
This process of speciation occurs when a geographic barrier, like a new ocean, separates two populations.
An event, such as a major meteorite impact, that is listed as a potential cause of a mass extinction.
What is the Impact Theory?
This type of selection favors the intermediate phenotypes, eliminating both extremes.
What is stabilizing selection?
Structures that have no function but are homologous to an ancestor, like the tiny leg bones in a whale.
What are vestigial structures?
The specific type of primate—which includes Gibbons, Gorillas, and Chimpanzees—that humans are listed as being closest to.
What are apes (great apes)?
The evolutionary process that leads to analogous structures due to similar adaptations in organisms that are not closely related.
What is convergent evolution?
This is NOT a type of natural selection because it involves humans selecting which traits are passed on.
What is artificial selection?
This is the phenomenon of genetic drift where a small group of individuals leaves and establishes a new, isolated population.
What is the founder effect?
This property of an organism's body, such as the absence of bone or shell, is the primary reason the majority of life does not fossilize.
The term for the human branch of the primate family tree, including H. habilis and H. sapiens.
What are Hominins?
The principle that states that older fossils are found in deeper layers of the Earth.
The term for an organism's genetic contribution to the next generation, which is the true definition of "fittest."
What is evolutionary fitness?
A scenario where two male elk lock antlers to secure the right to mate is a clear example of this specific mechanism of nonrandom mating.
What is sexual selection?
This line of evidence shows many species start off with similar development patterns due to shared ancient genetic instructions.
What are embryonic development patterns?
Which animal are humans most closely related to?
What is a chimpanzee?
The fixed, unchangeable rate at which a radioactive isotope decays, which is essential for absolute dating.
The two types of sexual selection.
What are mate choice and fight for the right to mate?