Breathe airy biology again in underwater activity to major while for, nostril has self-evident profit in coping. As to how evolution comes, drag in arrives length of bone of the upper jaw, neck position and nostril mouth position, concern how to go up directly pursue.
Human skull, the upper jaw is the shortest, the head is in vertebral and perpendicular position for the most part, neck can finite look up, nostril is in the front.
Bovine skull, the upper jaw is in very long, nostril position becomes the upper jaw upper part. Because major moment ox lowers his head, nostril is so major time is gadarene. Swim when the ox, the neck can look up to let the head and vertebral parallel, look up moment nostril has been in body coping, pose of buffalo natant moment is very typical.
Original whale kind skull, the upper jaw is very long, the neck secures vertebral and parallel position, already fundamental shift went to nostril coping.
Finally, contemporary and cetacean, the head is lengthened further, can occupy body 1/3, the neck was done not have almost, the head is secured with vertebral and parallel position, the mouth of nostril is farther upgrade move.
In addition, cetacean nostril is not to be on the back, remain in the top of head. Look cetacean from appearance back and head do not have apparent end, but it is on skeleton by what distinguish apparently. Say to a form version is only on the back, after all the object of popular science data is the mankind, major person mentions the top of head to be able to consider as vertebral parallel outspread position, namely cetacean mouth that position, say nostril does not have a person to be able to be misunderstood on the back.
