How blue whale evolved to size of a Boeing 737

Geronimo Vena
Mag 25, 2017

And by growing large, the whales could migrate thousands of miles to munch on krill in other parts of the globe. Fossil records show that ancient whales were much smaller than the now living behemoths. In this way, the researchers stated, baleen whales' channel nourishing frameworks, which developed around 30 million years prior, seem to have set the phase for significant size increments once rich wellsprings of prey wound up plainly packed specifically areas and times of the year.

A new study claims that an "evolutionary jump" after the most recent ice age caused the to become giants simply so they could eat more krill.

The mixture of nutrients resulted in more food for large whales to eat. This promotes the primary production of plant life, which in turn feeds the krill and allows them to assemble in enormous swarms. Scientists have discovered a modern blue whale as big as 100 feet long - being the largest creature ever on Earth. The baleen filter looks like bristles of a comb and is made up of keratin - the same stuff in our fingernails. With the water trickling out, the filters catch and capture the krill or fish.

This efficient technique alone would not have been sufficient for big whales to win out.

But according to Stanford University researcher Jeremy Goldbogen, it can't be the only reason whales got so big. On the list of the planet's most massive living creatures, the blue whale shares the top ranks with most other species of baleen whales alive today.

Pyenson notes that larger whales appeared in several different lineages around the same time, suggesting that massive size was somehow advantageous during that timeframe. This resulted in not only increased runoff, but also greater ocean nutrients. Those deep waters are often full of nutrients and food for the whales.

After looking at fossil data in ocean sediments, the scientists ultimately concluded that whales expanded in size as a response to a change in the way their food supply was distributed in the ocean. The skulls of this kind of whales alone are bigger than mini vans and could fit more than five people inside. "So for every gulp, they're getting tremendous amounts of energy" states Goldbogen. But, the paper says, the projected "climate-driven changes to ocean ecosystem structure, diversity, and productivity presage a decrease in critical habitat for large-bodied baleen whales and other suspension feeding vertebrates, highlighting the ecological vulnerability of these giants operating on an energetic knife-edge". Smaller whales would have benefited in circumstances where there was lots of swimming around to be done in the search for food.

The Scientists go back to the time of Ice Age when the Earth especially the Ocean has undergone huge change climate and environment change.

Olivier Lambert, a palaeontologist from the Royal Belgian Institute of Natural Sciences, who was not involved in the study, said the research provided a convincing scenario for one of the last stages in the evolution of size among baleen whales.

The fossils included in the analysis represented species dating back to the earliest baleen whales, which lived more than 30 million years ago. But he said the lack of fossils in certain time periods is an issue. With this very effective method, a lot of food can be consumed in one go so long as there are large pockets of food available in the first place - which was the case under the conditions mentioned.

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