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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.
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.
In palaeontology, the evidence for species and evolution comes mainly from the comparative anatomy of fossils. A chronospecies is defined in a single lineage (solid line) whose morphology changes with time. At some point, palaeontologists judge that enough change has occurred that two forms (A and B), separated in time and anatomy, once existed.
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]
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
On the other hand, under the composite species concept [17] a species continues through a lineage split if only one of the two resulting lineages acquires a new character, an event that is sometimes called speciation through "budding". The one that has a new character is now a new species but the other lineage, the one that looks identical to ...
A relationship between mean cell number and cell number variation was established following a law possessing an exponent of 2 upon a variety of multicellular eutelic taxa. [7] Hydatina senta (Phylum Rotifera, Order Bdelloidea) is a species of rotifers which demonstrate the most complete cell constancy of any species studied before 1912. [8]
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 ...