JUN 17, 2017 6:37 AM PDT

Here's How Baleen Whales Got to Be So Large

WRITTEN BY: Anthony Bouchard

Most people have never had the opportunity to see some of the largest marine mammals on the planet in person. Baleen whales, especially those of the blue whale and humpback whale species, are perhaps the best examples of some of the world’s largest marine animals.

On average, a blue whale can grow to be around 82 feet long and weigh around 300,000 pounds, but science demands answers for how in the world such a creature evolved to get so large, and a new study published in the Proceedings of the National Academy of Sciences finally takes a closer look into this unanswered question.

Baleen whales are typically massive compared to most other land and marine mammal species. Now, science tells us why.

Image Credit: Skeeze/Pixabay

All baleen whales lack any actual teeth; instead, they have baleen, which is a type of filter-feeding system. It enables the whale to take one massive rush of water into their mouths and then push the water back out through their baleen without allowing any prey that might have been captured to escape.

They prey mostly on smaller creatures, like krill, so it’s a prodding question as to why evolution has called on blue whales to be so large when, clearly, they wouldn’t need to be to continue eating the prey they eat today.

A closer look into at least 140 baleen whale fossils spanning several different species revealed some clues as to what might be going on here. Some the fossils represented species that are alive today, while most were extinct. The goal of looking at extinct species, in addition to modern species, was to learn more about how the creature evolved over time.

What the research indeed pointed out was that baleen whales weren’t always as large as they are today; in fact, they’re getting bigger today than they ever were before.

Related: Humpback whale 'super-groups' are popping up everywhere, and scientists don't know why

A few million years ago, whales were averaging lengths of around 16-32 feet, but that’s still not anywhere close to the blue whale’s massive 82-foot average length figure. Interestingly, the start of the overgrowth of these marine beasts seems to have occurred in several different species at around the same point in time, which was a red flag for the researchers.

It just so happens that the time period where all these baleen whales started going through growth spurts was at the time that the world was going through a major climate change shift that changed the ecosystem of the sea and made it a necessity for the creatures to have to travel longer distances in the ocean to find food.

Food that was typically easy to find was being swept away more easily by ocean currents and winds, moving the prey around to new settling points around the world. Now, baleen whales had to do a lot more traveling just to get to their food.

Related: This beached whale had a stomach full of plastic bags

Evolution took things from here, resizing the body of several baleen whales to make them a better fit for these longer, global trips. By having a significantly larger body, baleen whales now had the massive muscle density necessary to help these creatures swim for longer periods of time without becoming over-exhausted.

As a plus, being larger makes the trip seem shorter – just imagine, it only takes you a few seconds to walk from one side of your living room to the other, but it would take an ant several minutes. In terms of transportation, size does matter.

Another factor that may have had an impact is the fact that larger animals simply don't make good prey for other animals. With that in mind, larger baleen whales had better survival chances than smaller ones, so the big size eventualyl reigned surpreme.

Related: Humpack whale calves 'whisper' to their mothers to avoid predation

What the research points out is that climate change had a major impact on baleen whale body size at least once in Earth’s history, and it raises the question of what could happen to baleen whales in the face of the current climate change situation that we’re dealing with.

As ocean ecosystems are impacted on a global scale by modern climate change, could baleen whales go through yet another evolution? It’s possible, scientists say, but there’s no evidence to suggest that they’re going through any changes at this point in time.

Further research into modern baleen whales and their feeding and transportation habits could be made possible by modern tracking equipment and may help researchers find the answers they’re looking for.

Source: Wired, Wikipedia

About the Author
  • Fascinated by scientific discoveries and media, Anthony found his way here at LabRoots, where he would be able to dabble in the two. Anthony is a technology junkie that has vast experience in computer systems and automobile mechanics, as opposite as those sound.
You May Also Like
JAN 29, 2021
Microbiology
A 635-Million-Year-Old Microfungus That May Have Saved Life on Earth
JAN 29, 2021
A 635-Million-Year-Old Microfungus That May Have Saved Life on Earth
An international team reported finding a filamentous microfossil found in South China, shown in this image by Andrew Cza ...
FEB 25, 2021
Plants & Animals
Do Fish Have Personality?
FEB 25, 2021
Do Fish Have Personality?
Fish may seem to just swim around without much thought or character. But new research reported in Ecology and Evolution ...
MAR 02, 2021
Cell & Molecular Biology
Koala Retrovirus Can Rewrite the Genome & Trigger Cancer
MAR 02, 2021
Koala Retrovirus Can Rewrite the Genome & Trigger Cancer
Retroviruses can infect cells and insert themselves into the genetic code of their host. Sometime in the past 50,000 yea ...
MAR 14, 2021
Cell & Molecular Biology
Modern Animals Still Have Similarities to Our Weird Ancient Ancestors
MAR 14, 2021
Modern Animals Still Have Similarities to Our Weird Ancient Ancestors
Recent research involving ancient marine animals shows how humans and other animals still carry some of those animals' c ...
APR 18, 2021
Plants & Animals
Dogs Can Sniff Out COVID-19 Cases
APR 18, 2021
Dogs Can Sniff Out COVID-19 Cases
Dogs help us in a lot of ways. Now they may help us get back to normal after the pandemic by using their exceptional abi ...
MAY 02, 2021
Cell & Molecular Biology
Coral Cells Can Spit Out the Symbionts They Don't Want
MAY 02, 2021
Coral Cells Can Spit Out the Symbionts They Don't Want
Some microalgae are symbionts, like dinoflagellates that live in coral. A symbiotic sea anemone is seen in this image by ...
Loading Comments...