The differences between dolphins and porpoises (and how you can be cool to both)

Two-minute read

I thought I’d get ahead of the snowstorm of communications I anticipate receiving on this matter. If you’ve heard the first episode of my podcast you’ll know I have a particular fondness for this subject.

One thing I didn’t mention in the show was the fact that porpoises have little ridges on their dorsal fins. We still don’t know what they’re for but there are a couple of theories. Some think they’re similar to the bumps all over a humpback whale’s head and fins.

Technically called tubicles, scientists think having these round protrusions helps the animal reduce drag. Basically, the tubicles create areas of low pressure that let the pectoral fins slice through the water with minimal resistance.

It might be the case that having bumpy fins makes a porpoise more hydrodynamic. But there’s another idea going around. Under close scrutiny it appears the sequence of ridges is slightly different on every porpoise.

There’s a chance porpoises can recognise others of their species by rubbing up against the raised bumps. We can’t be certain though. If I had to guess I’d say it’s the hydrodynamics thing but honestly it could be a third thing nobody’s even thought of yet.

In terms of where porpoises sit on the family tree they’re more closely related to beluga whales than dolphins. I told you on the podcast there are seven species, although that won’t be the case for long.

I’m writing this in 2021. If you’re reading this and that isn’t the year any more there are probably only six species of porpoise now.

The vaquita is the smallest member of the family and as of this minute in time there are only 10 left. They get tangled in fishing nets and drown so frequently that the species basically has no hope.

It’s a sad note to end on but we need to start facing the reality that humans are having an impact on the other life on Earth. We’re insanely intelligent apes. Our species is essentially head animal at this school. I’m not saying we deserve that title, but that’s how it is. We have the opportunity to look at how changing our actions can benefit the world around us.

If I could advise one thing, the number one way to protect dolphins and porpoises is to eat less fish. In an ideal world I would recommend eating no fish. I get into this on the show in a big way but it bears repeating. A lot of animals die unnecessarily because of the fishing industry. Not to mention it’s disastrous for the environment.

The world’s smallest porpoise is all but gone because of human greed. All we can do is endeavour to prevent that happening to another species.