Terms : Hide Images
| 327544679 | Evolution: | Process in which a population changes over many generations or a generation-to-generation change in a population's frequencies of alleles or genotypes-a change in a population's genetic structure. | |
| 327544680 | Essentialism: | Plato's idea that any variations seen in plant and animal populations were merely imperfect representatives of "ideal' forms, where only the "perfect" forms were real. (Counters evolutionary thought). | |
| 327544681 | Natural Theology: | a philosophy dedicated to discovering the Creator's plan by studying nature. | |
| 327544682 | Taxonomy: | Founded by Carolus Linnaeus (1707-1778). A branch of biology concerned with naming and classifying the diverse forms of life in a binomial system. Deus creavit, Linnaeus disposuit. | |
| 327544683 | Fossils: | Relics or impressions of organisms from the past, hermetically sealed in rock. Paleontology: The study of fossils. | |
| 327544684 | Catastrophism: | Cuvier's view of the Earth's history where species were created and then destroyed during many catastrophes. (Counters evolutionary thought). | |
| 327544685 | Gradualism: | Geologist James Hutton's principal which holds that profound change is the cumulative product of slow but continuous processes. | |
| 327544686 | Uniformitarianism: | Charles Lyell's theory which incorporates gradualism and suggests that geological processes are so uniform that their rates and effects must balance out through time. | |
| 327544687 | Use and Disuse: | Lamarck's theory of the origin of hereditary traits. Aquired traits could be passed down to offspring | |
| 327544688 | Descent with modification: | Darwin's term for how organisms descend from some unknown prototype that lived in the remote past. The idea of phylogeny and a phylogenetic tree. | |
| 327544689 | Natural Selection: | differential success in reproduction, and its product is adaptation of organisms to their environment (Darwin). | |
| 327544690 | Biogeography: | Geographical distribution of species. | |
| 327544691 | Fossil record: | Evidence that the oldest known living organism is a prokaryote. This somewhat supports the theory that all organisms had a single celled ancestor. | |
| 327544692 | Comparative Anatomy: | Comparing anatomical structures that are similar in structure but not necessarily in function. *Like the limbs of various mammals (and other vertebrates) having the same bone structure. | |
| 327544693 | **Homologous structures: | Similar characteristics between different species. *See above | |
| 327544694 | **Analogous Structures: | Different structures in different species but with similar function. Wings of a bird are analogous to the wings of a bee. | |
| 327544695 | Vestigial organs: | Historic remnants of structures that had important functions in ancestors but are no longer essential. (Appendix, whale leg bones, and mole eyes) | |
| 327544696 | Molecular Biology: | Amino acid differences in hemoglobin, cytochrome C, DNA, etc... | |
| 327544697 | **Comparative Embryology: | Comparing the varying embryonic states in which species go through. Closely related organisms go through similar stages in the embryonic development. (Gill pouches) | |
| 327544698 | Phylogeny: | "replay" of the evolutionary history of a species. As in a phylogenetic tree. Ontogeny: The development of an organism | |
| 327544699 | Macroevolution: | Large-scale patterns, trends, and rates of change among families and other more inclusive groups of species. | |
| 327544700 | Microevolution: | Change in a gene pool of a population on the smallest scale brought about by mutation, natural selection, gene flow, and genetic drift. | |
| 327544701 | **Directional Selection: | Allele frequencies that are responsible for a range of phenotypic variation shift in a consistent direction. Due to a response to one or more changes in environmental conditions. Ex. Peppered moths | |
| 327544702 | **Stabilizing Selection: | Intermediate forms of a trait are favored and alleles that specify extreme forms are eliminated from a population. Counters the effects of mutation, gene flow, and genetic drift. | |
| 327544703 | **Disruptive Selection: | Both ends of the range of variation are favored and intermediate forms are selected against. | |
| 327544704 | **Sexual Selection & Dimorphism: | Favors the traits with no advantage for survival and reproduction, other than the fact that males or females prefer them. | |
| 327544705 | Genetic Drift: | random change in allele frequencies over generations, as brought about by chance alone. | |
| 327544706 | **Bottleneck effect: | severe reduction in population size, as brought about by intense selection pressure or natural calamity. | |
| 327544707 | Founder effect: | The establishment of a new population separate from an original population with a chance allele frequency. Seen on isolated islands. | |
| 327544708 | Speciation: | Changes in allele frequencies that are significant enough to mark the formation of daughter species from parent species. | |
| 327544709 | Prezygotic Barriers: . | Impede mating between species or hinder the fertilization of ova if members of different species attempt to mate. | |
| 327544710 | Habitat Isolation: (Pre-zygotic) | Where two species that live in different habitats within the same area may encounter each other, if at all, even though they are not geographically isolated. (Water and terrestrial habitats of the Genus Thamnophis). | |
| 327544711 | Behavioral Isolation: (Pre-zygotic) | Special signals that attract mates, as well as elaborate behavior unique to a species, are examples of behavioral isolation mechanisms. | |
| 327544712 | Temporal Isolation: (Pre-Zygotic) | Two species that breed during different times of the day, different seasons, or different years cannot mix their gametes | |
| 327544713 | Mechanical Isolation: (Pre-Zygotic) | Closely related species may attempt to mate, but fail consummate the act because they are anatomically incompatible. | |
| 327544714 | Gametic Isolation: (Pre-Zygotic) | Prevention of gametic fusion due to different factors. | |
| 327544715 | Postzygotic Barriers: | If a sperm cell from one species does fertilize an ovum of another species, then postzygotic barriers prevent the hybrid zygote from developing into a viable, fertile adult. Horse + donkey = sterile mule |
