Crossword clues for speciation
speciation
Douglas Harper's Etymology Dictionary
1906; see species + -ation. The verb speciate is a back-formation attested by 1961.
Wiktionary
n. 1 (context biology English) The process by which new distinct species evolve. 2 (context chemistry English) The formation of different (inorganic) species (especially of ions) as the environment changes
WordNet
n. the evolution of a biological species
Wikipedia
Speciation is the evolutionary process by which reproductively isolated biological populations evolve to become distinct species. The biologist Orator F. Cook was the first to coin the term 'speciation' for the splitting of lineages or " cladogenesis," as opposed to " anagenesis" or "phyletic evolution" occurring within lineages. Charles Darwin was the first to describe the role of natural selection in speciation.
There are four geographic modes of speciation in nature, based on the extent to which speciating populations are isolated from one another: allopatric, peripatric, parapatric, and sympatric. Speciation may also be induced artificially, through animal husbandry, agriculture, or laboratory experiments. Whether genetic drift is a minor or major contributor to speciation is the subject matter of much ongoing discussion.
It is widely appreciated that sexual selection could drive speciation in many clades, independently of natural selection. However the term “speciation”, in this context, tends to be used in two different, but not mutually exclusive senses. The first and most commonly used sense refers to the “birth” of new species. That is, the splitting of an existing species into two separate species, or the budding off of a new species from a parent species, both driven by a biological “fashion fad” (a preference for a feature, or features, in one or both sexes, that do not necessarily have any adaptive qualities). In the second sense, “speciation” refers the wide-spread tendency of sexual creatures to be grouped into clearly defined species, rather than forming a continuum of phenotypes both in time and space - which would be the more obvious or logical consequence of natural selection. This was indeed recognized by Darwin as problematic, and included in his On the Origin of Species (1859), under the heading “Difficulties with the Theory”. There are several suggestions as to how mate choice might play a significant role in resolving Darwin’s dilemma.
Speciation is a process that occurs naturally in evolution and is modeled explicitly in some genetic algorithms.
Speciation in nature occurs when two similar reproducing beings evolve to become too dissimilar to share genetic information effectively or correctly. In the case of living organisms, they are incapable of mating to produce offspring. Interesting special cases of different species being able to breed exist, such as a horse and a donkey mating to produce a mule. However in this case the Mule is usually infertile, and so the genetic isolation of the two parent species is maintained.
In implementations of genetic search algorithms, the event of speciation is defined by some mathematical function that describes the similarity between two candidate solutions (usually described as individuals) in the population. If the result of the similarity is too low, the crossover operator is disallowed between those individuals.
Category:Evolutionary algorithms
Speciation may refer to:
- Speciation (biology), evolutionary process by which new biological species arise
- Speciation (chemistry), distribution of chemical elements
Usage examples of "speciation".
As for me, I am grateful for differentiation and speciation, but I cannot feel as separate an entity as I did a few years ago, before I was told these things, nor, I should think, can anyone else.
If they follow our protocol, it will be anaerobic life at first, then photosynthesis and the first exhalation of oxygen, then respiring life and the great burst of variation, then speciation, and, finally, some kind of consciousness.
The separation of the speakers by migrations had effects on language comparable to the speciation observed by Darwin on various islands of Galapagos.
The size of evolutionary steps, the exact scenario for speciation, is still debated.
No speciation, all working from one genetic blueprint, making a few hundred different forms.
Earth, they suspected the evolution of humanity had been the consequence of a number of speciation steps.
The pithecine form had proved effective and enduring, and there had been a great churning of speciation events, a radiation of ape people.
Rather, speciation relied on a group of animals being isolated from the larger population and put under pressure to survive.
Synthetic Speciation, by Dr Heribert Nilsson, Professor of Botany from the University of Lund, Sweden.
To give an example of the way man operates compared to other animals, consider speciation, which, as we know, tends to occur when a small group of animals gets separated from the rest of the herd by some geological upheaval, population pressure, food shortage, or whatever, and finds itself in a new environment with maybe something different going on.
If that trend held for long, Sax thought, it would lead to a kind of physicalization of class-a late emergence or retroactive unveiling of Marx's bleak vision-only more extreme than Marx, because now class distinctions would be exhibited as an actual physiological difference caused by a bimodal distribution, something almost akin to speciation.
If that trend held for long, Sax thought, it would lead to a kind of physicalization of class—a late emergence or retroactive unveiling of Marx’s bleak vision—only more extreme than Marx, because now class distinctions would be exhibited as an actual physiological difference caused by a bimodal distribution, something almost akin to speciation.
The paper was entitled "Frequencies of Biologic Contact According to Speciation Probabilities.
And we've already come across improbabilities that are way beyond this bound, such as Fred Hoyle's figure for the likelihood of the full complement of human proteins arising through chance, or Lee Spetner's for speciation and convergence.
Brock believes the mummies represent the first clear evidence of a human speciation event,” Merton said, hoping to move things along.