I know I usually talk about crocs, but this is too good not to share. A new giant basilosaurid whale with weird anatomy from the Eocene of Peru. Perucetus colossus is a peculiar animal. It's bones were incredibly thick and incredibly dense, very much unlike those of modern whales and even more extreme than even those of the thicker basilosaurids (aptly named Pachycetinae i.e. thick whales). These adaptations have been compared to modern manatees and dugongs. Know the weight range is highly dependent on what you base the math on. Using manatees as a proxy, you get a weight of "only" 85 tons....using extreme values for whales a whopping 340 tons. Mean values for whales a still really big 180 tons. This could indicate that Perucetus rivaled the Blue Whale as the worlds heaviest animal ever.
The ecology is poorly understood tho. We know basilosaurids preferred coastal waters, and with all the similarities to manatees it is reasonable to assume that Perucetus was a shallow water animal itself. It also likely wasn't the fastest swimmer. And the lack of a skull basically means we can't say much on its diet. We can wager a guess and say it wasn't a predator because, you know....it also likely wasn't a grazer. Cool as it would be, we don't really have herbivorous whales like that so its incredibly unlikely. The two more likely suggestions are that it lived on small animals burried in the ocean floor, sorta like a grey whale. Or that it was a scavenger like a sleeper shark (tho I find that suggestion far less likely, giving me scavenging T.rex vibes ngl). But again, once we get a skull we can talk about this better.
Sidenote I do find the name a little underwhelming. It's a bizarre animal and the best we could come up with is "Colossal whale from Peru". I'm also not a mammal person, but from what I'm being told the silhouette is a little exaggerated and it wasn't necessarily that thick in life.
Life reconstruction by A. Gennari, paper can be found here A heavyweight early whale pushes the boundaries of vertebrate morphology | Nature
Note this response to the paper, which shows that it likely substantially overestimated the mass of this species: https://peerj.com/articles/16978/
Extremes in organismal size have broad interest in ecology and evolution because organismal size dictates many traits of an organism’s biolo
Still a big boi though.
