Whales: What are they, anyway?

Whales are often misunderstood. Even in Moby dick, one of the most famous depictions of a whale, they're referred to as fish! This is completely inaccurate.

Whales are mammals. What makes them mammals is the presence mammary glands, so they make milk to feed their babies.

So the reason whales look so similar to certain fish like sharks is due to something called ‘convergent evolution’, where animals that are genetically different end up looking the same due to living in the same environment. 

Kinda like a ‘you can copy my homework, but change it so the teacher doesn’t notice’ type thing, lol.

They are what's called ‘twice-evolved’. You may have heard of tiktaalik, the first vertebrate to make it to land. Well, wayyy after he crawled out of the water came the earliest whale ancestor, Pakicetus.

Pakicetus was always destined for greatness. Even as a scruffy, furry little creature still just wading around the shallows, he had an inner ear structure like no other.

He had a very thick ear plate called a bulla, which is not found in any mammal lineage other than whales. It allows them to catch vibrations much more easily under water, and also serves as evidence that a creature is a whale when looking at fossils.

whales: go go grandpa!

Ancient whales are called ‘archaeocetes’ and we’ll get into those later, but modern whales as we know them, ‘neocetes’, are divided into two categories: odontocetes and mysticetes.

Now you may be able to guess the meaning of odontocetes, the toothed whales, but what about mysticetes? Maybe because they’re mystical?? (that was my first thought too).

The ‘mysti’ bit comes from the Greek word ‘mustax’, meaning moustache. There can be thick, bristle like hairs on the upper lip of some whales. The first guy to notice this was Aristotle, who wrote about it in his book ‘Historia Annimalium’.

‘Cetes’ means sea monster, so their name means ‘moustached sea monster’. Gives a whole new perspective on those ancient maps and stuff

Mysticetes have baleen instead of teeth, which are plates made of keratin, the same stuff that makes our nails and hair. The blue whale, the largest animal in history (no strong competition yet except maybe from perucetus colossus or big chungus as I call him) is also a baleen whale.

The way they reach their enormous size is due to a technique called lunge feeding, where they find a spot with a bunch of krill, and lunge into it with their mouth open. They then close it and spit out the water through their baleen plates so only the krill remains.

Another point of great confusion is what exactly a dolphin is.

Simply put, all dolphins are whales, but not all whales are dolphins.

Dolphins are whats called a ‘wastebasket taxon’, which means a bunch of animals that aren’t really closely genetically related are still lumped together on the basis of physical features.

The features that all dolphins share are a distinct beak (rostrum), a melon (fluid filled organ in their forehead for echolocation) and conical teeth. Side note: if you’re wondering what a porpoise is, just remember that porpoises have spade shaped teeth while dolphin teeth are conical.

Nowadays I see a lot of people out there hate on dolphins a lot. Which I think is really dumb! Since they're so different, dolphins have way different levels of intelligence and social behaviour.

The way intelligence is measured in animals is using the encephalization quotient. ‘Cephalo’ comes from the Greek word ‘kephale’, which means head. So this is the brain to body mass ratio.

This varies greatly amongst all cetaceans, including dolphins. So creatures like the ganges river dolphin are about as smart as a dog, whereas orcas have ‘near human’ levels of intelligence. (I think theyre better than humans tbf).

Im not gonna get into all the dolphin hater arguments, but just remember that it’s a. not applicable to all dolphins, and b. why are we judging them by human standards? Like would you judge an chimp or cat in the same way?

Probably going to make a whole post about this one and how they need our help way more than our hate.

The last confusion ill clear up is how whales produce sound. So starting with toothed whales: they use very high frequencies. They produce sound through a structure called the phonic lips which are at the top of their blowhole.

These sounds are so high pitched that sperm whales actually use them to attack giant squid while hunting in the depths. Baleen whales use very low frequencies, using their larynx to make a majestic, deep rumble through the waters.

So that’s the end of my post! This will allow anyone who’s new to whales get the gist of things and make my later posts easier to understand. Hope it was fun to read and feel free to ask me any questions you might have (I'm only a college student rn so I'm an enthusiast, not a professional, but I will do my best)