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Mentum
The term mentum can refer to several anatomical structures near the mouth of an animal: *The median plate of an insect's labium. *The protruding part of the human chin. *A certain thin projection of the soft parts of the animal, below the mouth, in the family Pyramidellidae Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs. The great majority of species of pyrams are micromol .... References {{set index article ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Insect Mouthparts
Insects have arthropod mouthparts, mouthparts that may vary greatly across insect species, as they are adapted to particular modes of feeding. The earliest insects had chewing mouthparts. Most specialisation of mouthparts are for piercing and sucking, and this mode of feeding has evolved a number of times independently. For example, mosquitoes (which are true flies) and aphids (which are Hemiptera, true bugs) both pierce and suck, though female mosquitoes feed on animal blood whereas aphids feed on plant fluids. Evolution Like most external features of arthropods, the mouthparts of Hexapoda are highly derived. Insect mouthparts show a multitude of different functional mechanisms across the wide diversity of insect species. It is common for significant Homology (biology), homology to be conserved, with matching structures forming from matching Primordium, primordia, and having the same evolutionary origin. However, even if structures are almost physically and functionally identica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chin
The chin is the forward pointed part of the anterior mandible (List_of_human_anatomical_regions#Regions, mental region) below the lower lip. A fully developed human skull has a chin of between 0.7 cm and 1.1 cm. Evolution The presence of a well-developed chin is considered to be one of the morphological characteristics of ''Homo sapiens'' that Neanderthal anatomy#Distinguishing physical traits, differentiates them from other human ancestors such as the closely related Neanderthal, Neanderthals. Early human ancestors have varied Mandibular symphysis, symphysial morphology, but none of them have a well-developed chin. The origin of the chin is traditionally associated with the anterior–posterior breadth shortening of the dental arch or tooth row; however, its general mechanical or functional advantage during feeding, developmental origin, and link with human speech, physiology, and social influence are highly debated. Functional perspectives Robinson (1913) suggests that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
