choana उदाहरण वाक्य

उदाहरण वाक्य

1. Various suggestions had been put forward including that the choana was homologous to either the posterior or anterior nostril of non-tetrapods, that it had  budded off from one of these passages, or that it was an entirely novel form, unrelated to either of the other nostrils.
2. Through convergent evolution, lungfishes have evolved internal nostrils similar to the tetrapods'choana, and a brain with certain similarities to the lissamphibian brain ( except from the Queensland lungfish, which branched off in its own direction about 277 million years ago and has a brain resembling that of the Latimeria ).
3. The character state of the nostrils of " Kenichthys " demonstrates that the vertebrate choana did in fact evolve by migration of the posterior external nostril around the jaw and up onto the roof of the mouth . " Kenichthys " suggests that this migration took place on the route between the premaxilla and the maxilla.
4. On Long's 1986 expedition to Gogo the first relatively complete skull of " Gogonasus " was found by Chris Nelson and after being prepared solved a scientific controversy by showing that the inner large fangs of the coronoid bones did not insert into the choana of the palate ( Long 1988 ) as had been suggested by Rosen et al . ( 1981 ) for " Eusthenopteron ".
5. Such evidence is now available : a small lobe-finned fish called " Kenichthys ", found in China and dated at around 395 million years old, represents evolution " caught in mid-act ", with the maxilla and premaxilla separated and an aperture & mdash; the incipient choana & mdash; on the lip in between the two bones . " Kenichthys " is more closely related to tetrapods than is the coelacanth, which has only external nares; it thus represents an intermediate stage in the evolution of the tetrapod condition.