Carbon dating experiment
allopatric speciation: Speciation that occurs when two or more populations of a species are geographically isolated from one another sufficiently that they do not interbreed. There are 20 main amino acids in the proteins of living things, and the properties of a protein are determined by its particular amino acid sequence.amino acid sequence: A series of amino acids, the building blocks of proteins, usually coded for by DNA.algae: An umbrella term for various simple organisms that contain chlorophyll (and can therefore carry out photosynthesis) and live in aquatic habitats and in moist situations on land. Algae range from macroscopic seaweeds such as giant kelp, which frequently exceeds 30 m in length, to microscopic filamentous and single-celled forms such as Spirogyra and Chlorella. For example, if a gene determines the seed color of peas, one allele of that gene may produce green seeds and another allele produce yellow seeds.In a diploid cell there are usually two alleles of any one gene (one from each parent).
analogous structures: Structures in different species that look alike or perform similar functions (e.g., the wings of butterflies and the wings of birds) that have evolved convergently but do not develop from similar groups of embryological tissues, and that have not evolved from similar structures known to be shared by common ancestors. Note: The recent discovery of deep genetic homologies has brought new interest, new information, and discussion to the classical concepts of analogous and homologous structures.adaptive landscape: A graph of the average fitness of a population in relation to the frequencies of genotypes in it.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.The amnion surrounds the embryo with a watery substance, and is probably an adaptation for breeding on land.amphibians: The class of vertebrates that contains the frogs, toads, newts, and salamanders.