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In biology and botany, indeterminate growth is growth that is not terminated, in contrast to determinate growth that stops once a genetically predetermined structure has completely formed. Thus, a plant that grows and produces flowers and fruit until killed by frost or some other external factor is called indeterminate.
The shape of their skull does not change into adulthood (only increasing in size), due to sexual dimorphism and an evolutionary change in the timing of development. [ 39 ] In some groups, such as the insect families Gerridae , Delphacidae and Carabidae , energy costs result in neoteny; many species in these families have small , neotenous wings ...
A dragonfly in its final moult, undergoing metamorphosis, it begins transforming from its nymph form to an adult. Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. [1]
Modular organisms [3] have indeterminate growth forms (life stages not set) through repeated iteration of genetically identical modules (or individuals), and it can be difficult to distinguish between the colony as a whole and the modules within. [4] In the latter case, modules may have specific functions within the colony.
Despeciation – Loss of a species of animal due to its combining with another species; Anagenesis – Gradual evolutionary change in a species without splitting; Extinction – Termination of a taxon by the death of its last member; Microevolution – Change in allele frequencies that occurs over time within a population
There are numerous species of cichlids that demonstrate dramatic variations in morphology. Given the right circumstances, and enough time, evolution leads to the emergence of new species. Scientists have struggled to find a precise and all-inclusive definition of species. Ernst Mayr defined a species as a population or group of populations ...
Here, a species starts with the acquisition of a character and ends when another change is fixed in its lineage. This process - of one lineage turning into what is afterwards seen as another species because of the fixation of a novel character - is often called anagenesis.
In his book The Material Basis of Evolution (1940) he wrote "the change from species to species is not a change involving more and more additional atomistic changes, but a complete change of the primary pattern or reaction system into a new one, which afterwards may again produce intraspecific variation by micromutation." Goldschmidt believed ...