Post by Radrook Admin on Sept 29, 2019 21:43:51 GMT -5
Morphological Similarities don't Imply Common Descent
The reason I post this is because there is a video on youtube is erroneously using physical similarities as invariable evidence that certain animals are related. Please note that such an idea is not an official evolutionary teaching. Instead, many similarities between animals are attributed to convergent evolution where animals develop similar biological structures as adaptations to the similar or identical environments without any ancestral relationship between or among them whatsoever.
Definition
Convergent Evolution
noun
A kind of evolution wherein organisms evolve structures that have similar (analogous) structures or functions in spite of their evolutionary ancestors being very dissimilar or unrelated
Supplement
Convergent evolution refers to the kind of evolution wherein organisms evolve (analogous) structures or functions in spite of their evolutionary ancestors being very dissimilar or unrelated. Analogous structures pertain to those structures of unrelated (different) organisms having the same function but differing anatomical features. Because analogous structures differ in anatomy as well as developmental origin they do not implicate a common ancestral origin. The features or traits common in them evolve independently.
Examples are as follows:
the wings ofbats, birds, and insects evolved independently from each other but all are used to perform the function of flying
the complex eyes of vertebrates, cephalopods (squid and octopus), cubozoan jellyfish, and arthropods (insects, spiders, crustaceans) evolved separately, but all perform the function of vision
the smelling organs of the terrestrial coconut crab are similar to those of insects
the very similar shells of brachiopods and bivalve molluscs
prickles, thorns and spines have evolved independently to prevent or limit herbivory
plant hormones such as gibberellin and abscisic acid of plants and fungi
Also called:
convergence (evolutionary biology)
Compare:
divergent evolution
parallel evolution
See also:
analogy
analogous structures
evolution
www.biology-online.org/dictionary/Convergent_evolution
Convergent Evolution
noun
A kind of evolution wherein organisms evolve structures that have similar (analogous) structures or functions in spite of their evolutionary ancestors being very dissimilar or unrelated
Supplement
Convergent evolution refers to the kind of evolution wherein organisms evolve (analogous) structures or functions in spite of their evolutionary ancestors being very dissimilar or unrelated. Analogous structures pertain to those structures of unrelated (different) organisms having the same function but differing anatomical features. Because analogous structures differ in anatomy as well as developmental origin they do not implicate a common ancestral origin. The features or traits common in them evolve independently.
Examples are as follows:
the wings ofbats, birds, and insects evolved independently from each other but all are used to perform the function of flying
the complex eyes of vertebrates, cephalopods (squid and octopus), cubozoan jellyfish, and arthropods (insects, spiders, crustaceans) evolved separately, but all perform the function of vision
the smelling organs of the terrestrial coconut crab are similar to those of insects
the very similar shells of brachiopods and bivalve molluscs
prickles, thorns and spines have evolved independently to prevent or limit herbivory
plant hormones such as gibberellin and abscisic acid of plants and fungi
Also called:
convergence (evolutionary biology)
Compare:
divergent evolution
parallel evolution
See also:
analogy
analogous structures
evolution
www.biology-online.org/dictionary/Convergent_evolution
What is convergent evolution: how unrelated animals can look almost identical
www.zmescience.com/ecology/animals-ecology/story-convergent-evolution-unrelated-animals-can-look-almost-identical/