evolutionary biology

Examples of evolutionary biology in the following topics:

• Evolutionary Psychology

  • For instance, evolutionary biology researches the human body (such as the heart, lungs, or immune system) and how it adapts over time.
  • Proponents of evolutionary psychology suggest that it seeks to bridge the division between the human social sciences (such as psychology and sociology) and the natural sciences (such as biology, chemistry, and physics).
  • They argue that the psychology of human beings should be understood as a branch of biology, since humans are living organisms.
  • Evolutionary biology emerged as an academic discipline in the 1930s and 1940s, along with the study of animal behavior (ethology), both of which heavily influence the development of evolutionary psychology.
  • The field also draws on cognitive psychology, behavioral ecology, artificial intelligence, genetics, anthropology, archaeology, biology, and zoology.

• Spencer and Social Darwinism

  • This evolutionary process could be found at work, Spencer believed, throughout the cosmos.
  • However, writing after important developments in the field of biology, Spencer rejected the ideological assumptions of Comte's three-stage model and attempted to reformulate the theory of social progress in terms of evolutionary biology.
  • This social evolution, he argued, exemplifed the universal evolutionary process from simple, undifferentiated homogeneity to complex, differentiated heterogeneity.
  • Spencer's evolutionary ideas were based more directly on the evolutionary theory of Lamarck, who posited that organs are developed or diminished by use or disuse and that the resulting changes may be transmitted to future generations.
  • Spencer believed that this evolutionary mechanism was necessary to explain 'higher' evolution, especially the social development of humanity.

• Branches and Subdisciplines of Biology

  • The field of biology can be divided into various branches and subdisciplines, which leads to careers that result in more focused fields.
  • The scope of biology is broad and therefore contains many branches and subdisciplines.
  • Biology is the culmination of the achievements of the natural sciences from their inception to today.
  • Excitingly, it is the cradle of emerging sciences such as the biology of brain activity, genetic engineering of custom organisms, and the biology of evolution that uses the laboratory tools of molecular biology to retrace the earliest stages of life on earth.
  • Recognize the various subfields of biology; e.g. microbiology, genetics, evolutionary, etc.

• Limitations of Phylogenetic Trees

  • Limitations of phylogenetic trees include the inability to distinguish evolutionary time and relatedness between distinct species.
  • Another aspect of phylogenetic trees is that, unless otherwise indicated, the branches do not account for length of time, only the evolutionary order.

• The Fossil Record and the Evolution of the Modern Horse

  • The detailed fossil record of horses has provided insight into their evolutionary progress.
  • The sequence, from Eohippus to the modern horse (Equus), was popularized by Thomas Huxley and became one of the most widely known examples of a clear evolutionary progression.
  • Since then, as the number of equid fossils has increased, the actual evolutionary progression from Eohippus to Equus has been discovered to be much more complex and multibranched than was initially supposed.
  • Paleozoologists have been able to piece together a more complete outline of the modern horse's evolutionary lineage than that of any other animal.
  • This illustration shows an artist's renderings of species derived from fossils of the evolutionary history of the horse and its ancestors.

• Constructing an Animal Phylogenetic Tree

  • Phylogenetic trees are constructed according to the evolutionary relationships that exist between organisms based on homologous traits.
  • Evolutionary trees, or phylogeny, is the formal study of organisms and their evolutionary history with respect to each other.
  • Evolutionary trees are diagrams that show various biological species and their evolutionary relationships.
  • Evolutionary trees involve biological classification and use morphology to show relationships.
  • The evolutionary pathway is analyzed by the sequence similarity of these polymeric molecules.

• Molecular Analyses and Modern Phylogenetic Trees

  • The phylogenetic groupings are continually being debated and refined by evolutionary biologists.
  • Many evolutionary relationships in the modern tree have only recently been determined due to molecular evidence.
  • Evolutionary trees can be made by the determination of sequence information of similar genes in different organisms .
  • For constructing an evolutionary tree from proteins, for example, the sequences are aligned and then compared. rRNA (ribosomal RNA) is typically used to compare organisms since rRNA has a slower mutation rate and is a better source for evolutionary tree construction.
  • Advances in molecular biology and analysis of polymeric molecules such as DNA, RNA, and proteins have contributed to the development of phylogenetic trees.

• Whole-Genome Duplication

  • This may provide an evolutionary benefit to the organism by supplying it with multiple copies of a gene, thus, creating a greater possibility of functional and selectively favored genes.
  • Overall, paleopolyploidy can have both short-term and long-term evolutionary effects on an organism's fitness in the natural environment.
  • Wolfe & Shields hypothesized that this was actually the result of an entire genome duplication in the yeast's distant evolutionary history.
  • Based on these observations, they determined that Saccharomyces cerevisiae underwent a whole-genome duplication soon after its evolutionary split from Kluyveromyces, a genus of ascomycetous yeasts.

• Evolutionary Perspectives

• Phylogenetic Trees

  • Scientists use a tool called a phylogenetic tree, a type of diagram, to show the evolutionary pathways and connections among organisms.
  • Unlike a taxonomic classification diagram, a phylogenetic tree can be read like a map of evolutionary history.
  • In a rooted tree, the branching indicates evolutionary relationships .
  • Rooted phylogenetic trees can serve as a pathway to understanding evolutionary history.
  • Many disciplines within the study of biology contribute to understanding how past and present life evolved over time; together, these disciplines contribute to building, updating, and maintaining the "tree of life."