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This dictionary is one of a series covering the terminology and concepts used in important branches of science. The Facts on File Dictionary of Evolutionary Biology is planned as an additional source of information for students taking Advanced Placement (AP) Science courses in high schools. It will also be helpful to older students taking introductory college courses. This volume covers the topics important for an understanding of evolutionary theory, including classification, paleontology, genetics, molecular biology, and some geology. The definitions are intended to be clear and informative and, where possible, we have provided helpful diagrams and examples. The book also has a selection of short biographical entries for people who have made important contributions to the field. There are appendixes showing the classification of animals and plants. We have also added a short list of useful webpages and an informative bibliography. The book will be a helpful additional source of information for anyone studying the AP Biology course, especially the sections of the course covering Heredity and Evolution. However, we have not restricted the content to this syllabus. Evolutionary theory is an important, and sometimes controversial, area of modern science and we have tried to cover it in an interesting and informative way
[...]... Self-fertilization in plants autopolyploidy A type of polyploidy involving the multiplication of chromosome sets from only one species (see polyploid) Autopolyploids may arise from the fusion of diploid gametes that have resulted from the nondisjunction of chromosomes at MEIOSIS Alternatively, like allopolyploids, they may arise by the nondisjunction of chromatids during the mitotic division of a zygote Aves The. .. group selection; kin selection Alvarez theory The theory that the 7 amber MASS EXTINCTION at the end of the Cretaceous, including the complete extinction of the DINOSAURS, was caused by a large asteroid colliding with the Earth It was suggested that an asteroid of 10 km diameter could throw up enough dust to darken the sky for several years There is strong evidence for the theory: a high level of iridium... consisting of a flattened green thallus (GA- Anthozoa A class of cnidarians, the sea anemones and CORALS, in which the polyp 13 anthropoids ants See Hymenoptera is the only form and the medusa is absent The solitary sea anemone has numerous feathery tentacles Corals are colonial, with the polyp contained in a gelatinous matrix (the soft corals), a horny skeleton (the horny corals), or a skeleton of. .. depending on the number of cotyledons, giving the MONOCOTYLEDONAE and DICOTYLEDONAE The Angiosperms originated in the late Jurassic, but did not flourish until the Cretaceous Their ancestry remains obscure and BENNETTITALES, CAYTONIALES, CONIFEROPHYTA, and GNETOPHYTA have all been considered as possibilities The enormous adaptive radiation in the middle of the Cretaceous coincided with a similar evolution... DNA the amount of A is equal to the amount of T, and the amount of G equals the amount of C, but the amount of A + T does not equal the amount of C + G The A + T : G + C ratio is constant within a species but varies between species Basidiomycota (basidiomycetes) A phylum of FUNGI characterized by their spore-bearing structures (basidia) borne on a fertile layer (the hymenium) on the fruiting body The. .. has been suggested that the common ancestors of uintatheres and xenungulates may have been related to anagalids, which are relatives of rodents and rabbits by the absence of a nuclear spindle and leading to the production of daughter nuclei with unequal sets of chromosomes The ordered process of division, duplication of chromosomes, dissolution of nuclear membrane, and production of a spindle as in MITOSIS... classifications – the other two are EUKARYA and BACTERIA (In the Five Kingdoms classification scheme, it is a subkingdom of the BACTERIA.) They are bacterialike organisms and can be distinguished from Bacteria on the basis of biochemical differences in the nature of their lipid constituents, and their gene expression machinery Included in the Archaea are the methanogic (methane-producing), thermophilic... the Hadar region, Ethiopia, by Donald JOHANSON and Maurice Taieb They have also been found in Tanzania and Kenya and are dated between 2.9 million and 3.9 million years old The most famous of the first fossils is the partial skeleton of ‘Lucy’, named for the well-known Beatles song, ‘Lucy in the Sky with Diamonds’ A afarensis specimens show apelike features (the small body, and the shape and size of. .. During evolution, the success of the sporophyte may be its possession of a diploid number of chromosomes coupled alternative splicing See intron altruism Behavior by an animal that favors the survival of other animals of the same species at its own expense The most common example is that of parents putting themselves at risk, and sometimes losing their lives, to protect and save their offspring This... pairing The linking together of the two helical strands of DNA by bonds between complementary bases, adenine pairing with thymine and guanine pairing with cytosine The specific nature of base pairing enables accurate replication of the chromosomes and thus maintains the constant composition of the genetic material In pairing between DNA and RNA the uracil of RNA pairs with adenine base ratio The ratio of . alt="" The Facts On File DICTIONARY of EVOLUTIONARY BIOLOGY