What is the meaning of elucidating
ammonoid: Extinct relatives of cephalopods (squid, octopi, and chambered nautiluses), these mollusks had coiled shells and are found in the fossil record of the Cretaceous period.
amniotes: The group of reptiles, birds, and mammals.
Peaks on the landscape correspond to genotypic frequencies at which the average fitness is high, valleys to genotypic frequencies at which the average fitness is low. adaptive logic: A behavior has adaptive logic if it tends to increase the number of offspring that an individual contributes to the next and following generations.
If such a behavior is even partly genetically determined, it will tend to become widespread in the population.
artifact: An object made by humans that has been preserved and can be studied to learn about a particular time period.
artificial selection: The process by which humans breed animals and cultivate crops to ensure that future generations have specific desirable characteristics.
antibacterial: Having the ability to kill bacteria.
antibiotics: Substances that destroy or inhibit the growth of microorganisms, particularly disease-causing bacteria.
adaptive radiation: The diversification, over evolutionary time, of a species or group of species into several different species or subspecies that are typically adapted to different ecological niches (for example, Darwin's finches).
acquired trait: A phenotypic characteristic, acquired during growth and development, that is not genetically based and therefore cannot be passed on to the next generation (for example, the large muscles of a weightlifter).
adaptation: Any heritable characteristic of an organism that improves its ability to survive and reproduce in its environment.
In a diploid cell there are usually two alleles of any one gene (one from each parent).
Within a population there may be many different alleles of a gene; each has a unique nucleotide sequence.