The cretaceous period and the aftermath

Professor of biology at Amherst College, specializing in hummingbird and flower coevolution and the evolution of infectious diseases.

Others have since been caught and filmed in their natural habitat. All the genes in a population at a particular time. Among her research interests is a study of Nicaraguan Sign Language. The book looks at the effects of insecticides and pesticides on songbird populations throughout the United States.

A branching diagram that illustrates hypotheses about the evolutionary relationships among groups of organisms. His research includes work on Lucy Australopithecus afarensis. A biologist whose research has focused on endangered species, paleoenvironmental studies, and causes of extinction in North America, Africa, Madagascar, Hawaii, and the West Indies.

A paleontologist at Cambridge University in the U. Name given by Haeckel to recapitulation. Method of classification using both cladistic and phenetic classificatory principles. Species which depended on photosynthesis declined or became extinct as atmospheric particles blocked solar energy.

An acute infectious disease of the small intestine, caused by the bacterium Vibrio cholerae which is transmitted in drinking water contaminated by feces of a patient. The category of taxonomic classification between order and genus see taxon. Climatic cooling and drying during the Miocene led to several episodes where grassland ecosystems expanded and concomitant evolutionary diversifications of grazing mammals occurred.

The process by which a similar character evolves independently in two species. The T stands for Tertiary period.

The cretaceous period and the aftermath

Many scientists believe that the collision of a large asteroid or comet nucleus with Earth triggered the mass extinction of the dinosaurs and many other species near the end of the Cretaceous Period.

Although the descendants of nummulitids can be found today in the Indo-Pacific region, they show much less diversity. These include the evolutionary radiation of crabsbony fishsnails, and clams.

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In taxonomyreferring to the quantitatively measured difference between the phenetic appearance of two groups of individuals, such as populations or species phenetic distanceor the difference in their gene frequencies genetic distance.

The evolution of species from different taxonomic groups toward a similar form; the development of similar characteristics by taxonomically different organisms. Explained by the relative influences of intra- and inter-specific competition in sympatry and allopatry.

Tertiary Period

Reduviasporonitesthe most common supposed fungal spore, may be a fossilized alga ; [19] [30] the spike did not appear worldwide; [31] [32] and in many places it did not fall on the Permian—Triassic boundary.

Passerines began an explosive period of diversification during the Miocene. The impact would have released the same energy as trillion tons of TNT, or over a billion times the energy of the bombs dropped on Hiroshima.

Cells may exist as independent units of life, as in bacteria and protozoans, or they may form colonies or tissues, as in all plants and animals. A reduction in the average fitness of the members of a population because of the deleterious genes, or gene combinations, in the population.

His current research interests include hominid evolution, paleoecology, and taphonomy. The tendency of the different genes in a gene family to evolve in concert; that is, each gene locus in the family comes to have the same genetic variant. The reproductive cells in an organism, or the cells that produce the gametes.

A small, colonial, often planktonic marine animal that was very abundant in the oceans to million years ago; now extinct. Gastropods include snails and slugs that are marine, freshwater, and terrestrial.

The relation between the size of an organism and the size of any of its parts. An evolutionary biologist who has taught zoology and is the author of several books on evolution and science, including The Selfish Gene and The Blind Watchmaker.

The Cretaceous Tertiary Extinction event occurred 5 million years ago, and was a geologically short period of time.

It was known as the K-T extinction event, and has since become famous. The event is associated with the K-T boundary, which is a thin band of sedimentation found.

About 65 million years ago, at the tail end of the Cretaceous period, in a colossal example of what it means to be in the wrong place at the wrong time, a mile-wide asteroid (probably the largest of a series) collided with what is now the Yucatán Peninsula.

T1 - Aftermath of the end-Cretaceous mass extinction. T2 - Paleoceanography and Paleoclimatology. AU - Caldeira,K. AU - Rampino,M. R. PY - Y1 - N2 - In the aftermath of the Cretaceous/Tertiary (K/T) boundary event, pelagic carbonate productivity was.

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.

In addition, newly discovered fossil representatives of living groups of birds from the period shortly after the impact appear to have been ground dwellers, based on the proportions of their legs. Over 90 per cent of mammal species were wiped out by the same asteroid that killed the dinosaurs in the Cretaceous period 66 million years ago, significantly more than previously thought.

The cretaceous period and the aftermath
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Cretaceous - Wikipedia