PhylogeneticsStudy of evolutionary relationships between organismsOne small clade of fish, showing how venom has evolved multiple times.In biology, phylogenetics () is the study of the evolutionaryhistory of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, proteinamino acid sequences, and morphology.
EvolutionEvolution is the change in the heritable characteristics of biological populations over successive generations. It happens when individuals in a population vary in their genetic characteristics and in the numbers of their surviving offspring. Mutation introduces new genetic variation, and processes such as genetic drift, gene flow, and natural selection result in some genetic variants becoming more or less common over time.
Population geneticsSubfield of geneticsPopulation genetics is a subfield of genetics that deals with genetic differences within and among populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis.
ProteinBiomolecule consisting of chains of amino acid residuesA representation of the 3D structure of the protein myoglobin showing turquoise α-helices. This protein was the first to have its structure solved by X-ray crystallography. Toward the right-center among the coils, a prosthetic group called a heme group (shown in gray) with a bound oxygen molecule (red).Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acidresidues.
DNADeoxyribonucleic acid (pronunciation; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids.AdaptationEvolutionary processIn biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection.
RNAFamily of large biological moleculesA hairpin loop from a pre-mRNA. Highlighted are the nucleobases (green) and the ribose-phosphate backbone (blue). This is a single strand of RNA that folds back upon itself. Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA).Tree of life (biology)The tree of life or universal tree of life is a metaphor, conceptual model, and research tool used to explore the evolution of life and describe the relationships between organisms, both living and extinct, as described in a famous passage in Charles Darwin's On the Origin of Species (1859). The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth.
OrganismAn organism is any living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Several criteria, few of which are widely accepted, have been proposed to define what constitutes an organism. Among the most common is that an organism has autonomous reproduction, growth, and metabolism. This would exclude viruses, even though they evolve like organisms.
Complex traitsComplex traits, also known as polygenic or multigenic traits, are phenotypes determined by the interaction of multiple genetic and environmental factors. A central goal of contemporary genetics research is to understand the molecular mechanisms by which genetic variation influences complex traits.
Cell (biology)Basic unit of life formsThe cell is the basic structural and functional unit of all forms of life or organisms. The term comes from the Latin word cellula meaning 'small room'. A biological cell basically consists of a semipermeablecell membrane enclosing cytoplasm that contains genetic material. Most cells are only visible under a microscope.
HeredityHeredity, also called inheritance or biological inheritance, is the passing on of genetic information from parents to their offspring. It may occur through sexual or asexual reproduction, where new cells are produced from either individual cells underdoing cell division or two cells combining genomes, respectively. Through heredity, genetic variations in populations can accumulate and cause species to evolve by natural selection. The study of heredity in biology is genetics.*As an Amazon Associate I earn from qualifying purchases.