Portal:Evolutionary biology

The Evolutionary Biology Portal

Topics

Culture

Geography

Health

History

Mathematics

Nature

People

Philosophy

Religion

Society

Technology

Evolutionary biology is a sub-field of biology concerned with the origin and descent of species, as well as their change, multiplication, and diversity over time. Biologically, evolution is the change in the inherited traits of a population from generation to generation. These traits are the expression of genes that are copied and passed on to offspring during reproduction. Mutations in these genes can produce new or altered traits, resulting in heritable differences (genetic variation) between organisms. New traits can also come from transfer of genes between populations, as in migration, or between species, in horizontal gene transfer. Evolution occurs when these heritable differences become more common or rare in a population, either non-randomly through natural selection or randomly through genetic drift.

edit  watch  

Selected article

The Cretaceous–Paleogene extinction event was the large-scale mass extinction of animal and plant species in a geologically short period of time, approximately 66 million years ago (mya). It is widely known as the K–T extinction event and is associated with a geological signature, usually a thin band dated to that time and found in various parts of the world, known as the K–T boundary. K is the traditional abbreviation for the Cretaceous Period, and T is the abbreviation for the Tertiary Period. The event marks the end of the Mesozoic Era, and the beginning of the Cenozoic Era. Non-avian dinosaur fossils are only found below the K–T boundary and became extinct immediately before or during the event. A very small number of dinosaur fossils have been found above the K-T boundary, but they have been explained as reworked, that is, fossils that have been eroded from their original locations then preserved in later sedimentary layers. Mosasaurs, plesiosaurs, pterosaurs and many species of plants and invertebrates also became extinct. Mammalian and bird clades passed through the boundary with few extinctions, and radiation from those Maastrichtian clades occurred well past the boundary. Rates of extinction and radiation varied across different clades of organisms. Many scientists theorize that the K-T extinctions were caused by one or more catastrophic events such as massive asteroid impacts or increased volcanic activity. Several impact craters and massive volcanic activity in the Deccan traps have been dated to the approximate time of the extinction event. These geological events may have reduced sunlight and hindered photosynthesis, leading to a massive disruption in Earth's ecology. Other researchers believe the extinction was more gradual, resulting from slower changes in sea level or climate.

edit  watch  

Selected picture

Dusky Seaside Sparrow

Orange Band, the last Dusky Seaside Sparrow died in 1987 in a captive facility in the Walt Disney World Resort

Evolutionary biology

Evolutionary biologists • Eugenics • Evolutionary biology literature • Evolutionary dynamics • Evolutionary game theory • Extinction • History of evolutionary biology • Human evolution • Microbial population biology • Molecular evolution • Mutation • Paleontology • Phylogenetics • Population genetics • Evolutionary psychology • Selection • Sociobiology • Speciation • Symbiosis • Tree of life •

• ...that adaptations enable living organisms to cope with environmental stresses and pressures?
• ...that maintained gene flow between two populations can also lead to a combination of the two gene pools, reducing the genetic variation between the two groups?
• ...that all forms of natural speciation have taken place over the course of evolution, though it still remains a subject of debate as to the relative importance of each mechanism in driving biodiversity?
• ...that despite the relative rarity of suitable conditions for fossilization, approximately 250,000 fossil species are known?
• ...that genetic sequence evidence thus allows inference and quantification of genetic relatedness between humans and other apes?
• ...that the human species has a common ancestor with the ape? (similar to above reference)

Here are some tasks awaiting attention:

• Improve: List of prehistoric mammals, List of extinct plants, Holocene extinction event
• Stubs: Acritarch | Analogy (biology) | Evolutionary arms race | Genetic erosion | Hoyle's fallacy | Macromutation | Maladaptation | Evolutionary capacitance | Evolutionary graph theory | Evolutionary landscape | Evolutionary taxonomy | Landrace | Law of Life (more...)
• Nominate and vote: Science collaboration of the month, Article Improvement Drive

WikiProjects connected with biology:

• Conservation worldwide
• Ecology
  • Extinction
• Ecoregions
• Evolutionary biology
  • Game theory
• History of Science
• Marine life
• Medicine
• Microbiology
• Molecular and Cellular Biology
• Neuroscience
• Tree of Life
  • Prokaryotes and Protists
  • Plants
  • Arthropods
  • Cephalopods
  • Gastropods
  • Fishes
  • Amphibians and Reptiles
  • Birds
  • Mammals
  • Human Genetic History
  • Viruses

A complete list of scientific WikiProjects can be found here. See also Wikispecies, a Wikimedia project dedicated to classification of biological species.

Template:/box-header

Evolutionary biology fields— Cladistics • Ecological genetics • Evolutionary development • Human evolution • Molecular evolution • Phylogenetics • Population genetics
Mechanisms— Natural selection • Genetic drift • Gene flow
Outcomes— Adaptation • Co-evolution • Co-operation • Speciation • Extinction
Research and history— Evidence of common descent • Evolutionary history of life • History of evolutionary thought • Modern evolutionary synthesis • Social effect of evolutionary theory • Objections to evolution
Applications — Evolutionary algorithm •

Related subjects

	90x63px
Biology	Chemistry	Earth sciences	History of science	Philosophy of science	Death
Science	Molecular Anthropology

Topics in biology

Biotechnology	Ecology	Extinction	Marine Life	Molecular and Cell Biology

• What are portals?
• List of portals
• Featured portals