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The term "homology" was first used in biology by the anatomist Richard Owen in 1843 when studying the similarities of vertebrate fins and limbs, defining it as the "same organ in different animals under every variety of form and function", [6] and contrasting it with the matching term "analogy" which he used to describe different structures ...
This system is used in many unrelated animals: ants, bees, and wasps, termites, naked mole-rat, Damaraland mole-rat, Synalpheus regalis shrimp, certain beetles, some gall thrips and some aphids. [191] Oxygenate blood came about in unrelated animals groups: vertebrates use iron and crustaceans and many mollusks use copper . [192]
(Fig. 2c) Evolution has caused enlargement and modification of these structures in some species, while it has caused the reduction and loss of them in other species. The modifications enable the insects to exploit a variety of food materials. Insect mouthparts and antennae are considered homologues of insect legs.
Whereas ordinary homology is seen in the pattern of structures such as limb bones of mammals that are evidently related, deep homology can apply to groups of animals that have quite dissimilar anatomy: vertebrates (with endoskeletons made of bone and cartilage) and arthropods (with exoskeletons made of chitin) nevertheless have limbs that are constructed using similar recipes or "algorithms".
Homology and analogy in mammals and insects: on the horizontal axis, the structures are homologous in morphology, but different in function due to differences in habitat. . On the vertical axis, the structures are analogous in function due to similar lifestyles but anatomically different with different phyloge
The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. [1] The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but the insect identity of the fossil has been contested. [3]
Homologous Hox genes in such different animals as insects and vertebrates control embryonic development and hence the form of adult bodies. These genes have been highly conserved through hundreds of millions of years of evolution.
The development of insect mouthparts from the primitive chewing mouthparts of a grasshopper in the centre (A), to the lapping type (B) of a bee, the siphoning type (C) of a butterfly and the sucking type (D) of a female mosquito. Legend: a, antennae; c, compound eye; lb, labium; lr, labrum; md, mandibles; mx, maxillae; hp hypopharynx.