Large Forehead Aids Sperm Whales in Aggressive Ramming

The strange forehead architecture of sperm whales has long been a matter of mystery and speculation. The marine mammals, which have the largest forehead in the animal kingdom, can hammer objects that are two times bigger in size without damaging their head or getting injured in the process, a new research suggests.

According to the study, there may be possibilities that the sperm whale's forehead may have ecologically evolved for the purpose of ramming. A particular section of the head, termed junk, can absorb and spread the stress of the impact, considerably reducing its impact. 

Many studies relate modern day sperm whales with even-toed ungulates from the artiodactyls order. It is believed that the gigantic marine creatures, which are mammals, once lived on land but took to water due to the abundant presence of food. In gradual course of time they underwent evolution that gave them their present physical form.

On the basis of the recent study that states whales are not impacted by forceful ramming, it is being speculated that this characteristic is reminiscent of artiodactyls like antelopes, goats, deer and sheep that have a tendency to ram their horns against each other in an act of dominance and competition. Sperm whales could have retained the same behavior.

There is a considerable difference between the head size of male and female whales, with that of the former being larger in ratio. Researchers have suggested that mating purposes, in particular competition among the males to get females, may have a relation to the size of the forehead.

It has been observed that male bull whales are known to butt heads as a sign of competition, and even aggression, in their quest to find a suitable mate. The size of the head has a major impact on the outcome of the ramming. These studies add further fuel to the new theory that large foreheads of sperm whales evolved to facilitate ramming.