I pulled the toy from the Random Object Randomogrifier and today it was a manatee, a little swimming spud, a potato that decided to glide around in the water. This is my daily drawing practice and I like that I get to come downstairs and do it with my art besties and my mom. A lot of folks my age do not have that. I am keeping the morning time honest.
What surprised me this morning was how many times mammals have said nope, I am going back to the water. We have already talked about whales and dolphins, how they share ancestry with hippos. We have talked about the seals, sea lions, and walruses that go back to bears and wolves. This manatee is the third one. These guys stepped off the main road with the elephants about 50 million years ago in the old Tethys Ocean area. That clade is Tethytheris. I was shocked that a manatee is closer to an elephant than to a dolphin.
Manatees did it different from the other marine mammals. Most ocean animals manage their water and salt through their kidneys and oils so they can wander way out into the open ocean. These guys still have to drink fresh water to keep their salt balance right so they have to stay along the coasts where rivers and springs come out. Forty million years ago their ancestors still had legs in the fossil record, then they grew out that round tail like a beaver and lost the back legs. The modern form has been around about 12,000 years, right about the same time North American animals were coming out of the Ice Age and the land bridge finally closed.
They are vegetarians where almost all the other ocean going mammals are carnivores. Vegetarians get gassy. These things use the gas for buoyancy. They collect it in their body and use it to float closer to the surface. That is going to be my story from now on too, if I am gassy, I am just trying to float. Sailors thought they looked like healthy girls on a rock so the group got named Serenia, they thought they were sirens.
The only thing that really bothers them now is us. They have no natural predators. Boat strikes scar their backs and pollution along the coasts makes it harder for them to stay where the fresh water is. The good news is their numbers came up. In 1991 there were about 1,267 in Florida and today it is about 8,350 in Florida and around 13,000 total between Florida and South America. They could even speciate someday because the groups are so far apart.
Click here to watch this episode of Sketch & Coffee
Also, if you, or a teacher friend, would like a 20-30 minute lesson plan about manatees, feel free to download and share this one:
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