reptiles are paraphyletic because birds are not classified in this group Phylogeny Trees -trying to figure out the true evolutionary relationships among organisms Definitions: ... Parallel evolution- organisms, with a recent common ancestor, look similar because they live in similar environments.
biology.ucsd.edu/classes/old.web.classes/bieb150.FA01/C... biology.ucsd.edu/classes/old.web.classes/bieb150.FA01/Classifying%20organisms.pdf
Species - Wikipedia, the free encyclopedia
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In biology, a species is: • a taxonomic rank (the basic rank of biological classification) or • a unit at that rank (in which case the plural is "species". This is sometimes abbreviated: "spec." o...
en.wikipedia.org/wiki/Species
Biologists name organisms according to their evolutionary history because this history is so informative. ... Elephant shrews were not closely related to shrews or to other mammal groups like rabbits, with which they had sometimes been lumped. ... Traits in separate lineages that are similar, not because of common ancestry,
evolution.berkeley.edu/evolibrary/news/080301_elephants... evolution.berkeley.edu/evolibrary/news/080301_elephantshrew
We now recognize six kingdoms: Plantae (plants), Animalia (animals), Fungi (fungi & moulds), Eubacteria (the bacteria – sometimes called Monera); Archaea (microbes similar to bacteria); ... Sharks and dolphins aren't closely related; they look similar because this is the most ergonomic design for an aquatic lifestyle.
www.wildlifeonline.me.uk/classifying_organisms.html www.wildlifeonline.me.uk/classifying_organisms.html
The goal is to use gene(s) that are sufficiently variable (due to natural genetic mutations that accumulate over evolutionary time) to be able to distinguish closely related organisms (say species within a genus), but not so variable that the sequences show little similarity even between close relatives.
www.okstate.edu/artsci/SPMO/faqs.htm
Linnaeus and Aristotle both based their systems of organization only on outward appearance, but today biologists use the classifcation system to group organisms together according to how they are related. Often, plants or micro-organisms might look very similar but not be closely related at all.
www.suite101.com/article.cfm/paleontology/29309
A species consists of individual organisms which are very similar in appearance, ... This species concept is much criticised because more recent genetic data reveal that genetically distinct populations may look very similar and, contrarily, large morphological differences sometimes exist between very closely-related populations.
www.newuniverse.co.uk/Species.html
Additionally, a recent study [19] has shown that the use of comparative genomics alone to determine whether or not a genomic region is likely to harbor a genic ORF can result in false negatives, since many transcribed elements may not be conserved across even closely related species.
ukpmc.ac.uk/articlerender.cgi?tool=pubmed&pubmedid=1909... ukpmc.ac.uk/articlerender.cgi?tool=pubmed&pubmedid=19096707
This occurs when organisms are not separated physically, but "choose" not to breed with each other thereby ... Dr Kandul and his colleagues found that if closely related species of Agrodiaetus are geographically separate, they tend to look quite similar. That is to say, they do not display a distinctive "team strip".
news.bbc.co.uk/2/hi/science/nature/4708459.stm
B. Biotic pathogens: living organisms ... Oomycetes. Look similar to 'true fungi', but not closely related. ... Not a large reduction in spray use, because threat of disease almost always present...
www.staff.ncl.ac.uk/ethan.hack/cplo.html