Evolution of mammalsThe evolution of mammals has passed through many stages since the first appearance of their synapsid ancestors in the Pennsylvanian sub-period of the late Carboniferous period. By the mid-Triassic, there were many synapsid species that looked like mammals. The lineage leading to today's mammals split up in the Jurassic; synapsids from this period include Dryolestes, more closely related to extant placentals and marsupials than to monotremes, as well as Ambondro, more closely related to monotremes.
Chimpanzee–human last common ancestorThe chimpanzee–human last common ancestor (CHLCA) is the last common ancestor shared by the extant Homo (human) and Pan (chimpanzee and bonobo) genera of Hominini. Estimates of the divergence date vary widely from thirteen to five million years ago. In human genetic studies, the CHLCA is useful as an anchor point for calculating single-nucleotide polymorphism (SNP) rates in human populations where chimpanzees are used as an outgroup, that is, as the extant species most genetically similar to Homo sapiens.
PaleopolyploidyPaleopolyploidy is the result of genome duplications which occurred at least several million years ago (MYA). Such an event could either double the genome of a single species (autopolyploidy) or combine those of two species (allopolyploidy). Because of functional redundancy, genes are rapidly silenced or lost from the duplicated genomes. Most paleopolyploids, through evolutionary time, have lost their polyploid status through a process called diploidization, and are currently considered diploids, e.g.
AncestorAn ancestor, also known as a forefather, fore-elder, or a forebear, is a parent or (recursively) the parent of an antecedent (i.e., a grandparent, great-grandparent, great-great-grandparent and so forth). Ancestor is "any person from whom one is descended. In law, the person from whom an estate has been inherited." Two individuals have a genetic relationship if one is the ancestor of the other or if they share a common ancestor. In evolutionary theory, species which share an evolutionary ancestor are said to be of common descent.
FinA fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fins are also used to increase surface areas for heat transfer purposes, or simply as ornamentation. Fins first evolved on fish as a means of locomotion. Fish fins are used to generate thrust and control the subsequent motion.
Plant morphologyPhytomorphology is the study of the physical form and external structure of plants. This is usually considered distinct from plant anatomy, which is the study of the internal structure of plants, especially at the microscopic level. Plant morphology is useful in the visual identification of plants. Recent studies in molecular biology started to investigate the molecular processes involved in determining the conservation and diversification of plant morphologies.
Genetic testingGenetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or through biochemical analysis to measure specific protein output. In a medical setting, genetic testing can be used to diagnose or rule out suspected genetic disorders, predict risks for specific conditions, or gain information that can be used to customize medical treatments based on an individual's genetic makeup.
Gene regulatory networkA gene (or genetic) regulatory network (GRN) is a collection of molecular regulators that interact with each other and with other substances in the cell to govern the gene expression levels of mRNA and proteins which, in turn, determine the function of the cell. GRN also play a central role in morphogenesis, the creation of body structures, which in turn is central to evolutionary developmental biology (evo-devo).
Gene knockoutGene knockouts (also known as gene deletion or gene inactivation) are a widely used genetic engineering technique that involves the targeted removal or inactivation of a specific gene within an organism's genome. This can be done through a variety of methods, including homologous recombination, CRISPR-Cas9, and TALENs. One of the main advantages of gene knockouts is that they allow researchers to study the function of a specific gene in vivo, and to understand the role of the gene in normal development and physiology as well as in the pathology of diseases.
TeleostTeleostei (ˌtɛliˈɒstiaɪ; Greek teleios "complete" + osteon "bone"), members of which are known as teleosts (ˈtɛliɒsts,_ˈtiːli-), is, by far, the largest infraclass in the class Actinopterygii, the ray-finned fishes, and contains 96% of all extant species of fish. Teleosts are arranged into about 40 orders and 448 families. Over 26,000 species have been described. Teleosts range from giant oarfish measuring or more, and ocean sunfish weighing over , to the minute male anglerfish Photocorynus spiniceps, just long.
