The Echo Hunter helps us comprehend the Whale Evolution a bit more

A 27 million year old fossil from a species named Echovenator Sandersi, nicknamed Echo Hunter, had been found 15 years ago in South Carolina. Recently, it had been discovered that the features in its inner ear indicated that it could hear sounds too high pitched for the human ear. This species is a relative of the modern toothed whales like dolphins, porpoises, and sperm whales. Based on the Echo Hunter's skull and cranial features they were able to tell if this species could echo locate or not. By examining the inner ear, researchers found evidence of its ability to receive high frequencies. A soft tissue structure called the basilar membrane, not present on the fossil, but indicated by other parts of the ear to be of size and thickness consistent of high frequency hearing. A thick, bony part of the cochlea also provided further evidence of this ability. Toothed whales use echolocation to hunt for prey by emitting a series of high frequency chirps and navigating based on echoes. Dr Uhen believed that the development of high frequency hearing is a nice illustration of natural selection. Because of this newly discovered information, we now know that the use of navigational technique of echolocation goes back millions of years earlier in whales than previously known. 

http://www.nytimes.com/2016/08/05/science/echo-hunter-whale.html?rref=collection%2Fcolumn%2Ftrilobites&action=click&contentCollection=science&region=stream&module=stream_unit&version=latest&contentPlacement=2&pgtype=collection

http://www.eurekalert.org/pub_releases/2016-08/cp-wuh072816.php

Rare Whale Discovered in Pacific

Scientists have discovered a rare new whale species within the waters stretching from Japan to Aleutian islands in Alaska. The new discovery shows just how much of the ocean is still yet to be explored and studied by humans. The new species which has not yet be named is approximately twenty four feet long as an adult. It has a slight different head shape and location of its dorsal fin as a Baird whale or the Arnoux beaked whale which are all in the genus and closely related. 

The new found whale has not been seen or found alive. All of the specimens have either washed ashore or been caught by Japanese fishermen. Further research needs to be done to find a common ancestor between the rare whale and the Arnoux beaked whale. Now that the whale has been discovered scientist can work together to protect it.

Acrobatic whale feeding

 

http://www.nytimes.com/2012/12/04/science/acrobatic-blue-whales-can-sneak-up-on-krill.html?_r=0
New whale feeding technique

To capture enough food, blue whales use a technique called lunge feeding. They take enormous gulps of water, then let it pass through comb-like mouth filters called baleen, keeping krill behind for consumption. This allows the massive whales to get thousands upon thousands of krill, enough to feed them.

However, a new study reports, they also do an acrobatic roll to help them capture krill more effectively.  Researchers explain that the whales sometimes roll 180 degrees, so their backs face the seafloor as they accelerate and move forward to open their mouths for a lunge. This lunge is simply a more effective way of attacking the massive packs of krill. More effective means more food.

 

This picture is of a blue whale using the more effective method to eat krill

 

Two of the main researchers of this project noted that "They engulf from right beneath the krill patch so they are less likely to be seen" "This minimizes the escape of the krill". After completing the roll the whale flips another 180 degrees and continues on swimming normally. The process in whole takes about 20 to 30 seconds, but the weird thing is only about half the whales did this and of the whales that did it was only used about 10% of the time. Now you may wonder why so little? Well one thought is that it is only used for small patches of krill to maximize the catch. www.blue-whale.info/Blue_Whale_Diet.html This site is the all know about the blue whale and all of its feeding techniques.

 

My opinion of this would be that I am wondering why the blue whales only use their more effective method about 10% if they use it at all. I am curious to see why they don't use it more, seeing as it would mean more food. There must be some reason they aren't and that's what I want to know.