Search results
Results From The WOW.Com Content Network
Involution is the shrinking or return of an organ to a former size. At a cellular level, involution is characterized by the process of proteolysis of the basement membrane (basal lamina), leading to epithelial regression and apoptosis, with accompanying stromal fibrosis. The consequent reduction in cell number and reorganization of stromal ...
In developmental biology, pattern formation refers to the generation of complex organizations of cell fates in space and time. The role of genes in pattern formation is an aspect of morphogenesis , the creation of diverse anatomies from similar genes, now being explored in the science of evolutionary developmental biology or evo-devo.
The pygmy mammoth is an example of insular dwarfism, a case of Foster's rule, its unusually small body size an adaptation to the limited resources of its island home.. A biological rule or biological law is a generalized law, principle, or rule of thumb formulated to describe patterns observed in living organisms.
Also called functionalism. The Darwinian view that many or most physiological and behavioral traits of organisms are adaptations that have evolved for specific functions or for specific reasons (as opposed to being byproducts of the evolution of other traits, consequences of biological constraints, or the result of random variation). adaptive radiation The simultaneous or near-simultaneous ...
Phylogenies showing the terminology used to describe different patterns of ancestral and derived trait states. [1] Imaginary cladogram. [2] The yellow mask is a plesiomorphy for each living masked species, because it is ancestral. [2] It is also a symplesiomorphy for them.
The extinction event may have been more severe for the larger-bodied species, leaving only species of smaller-bodied animals behind. [1] As such, organisms in the smaller species which then make up the recovering ecosystem, will take time to evolve larger bodies to replace the extinct species and re-occupy the vacant ecological niche for a large-bodied animal. [1]
An example of a botanical genetic polymorphism is heterostyly, in which flowers occur in different forms with different arrangements of the pistils and the stamens. The system is called heteromorphic self-incompatibility , and the general 'strategy' of stamens separated from pistils is known as herkogamy .
Reticulate patterns can be found in the phylogenetic reconstructions of biodiversity lineages obtained by comparing the characteristics of organisms. [2] Reticulation processes can potentially be convergent and divergent at the same time. [3] Reticulate evolution indicates the lack of independence between two evolutionary lineages. [1]