Lungfish
by John T.
The Lungfish is an air breathing, eel like fish. It’s very long and some species can grow to be six feet long. While it can be found all over the world, the sub-species that I picked is native to Africa, which is why they call it the African Lungfish. It has a thin- shaped body with a large tail surrounding the end of its body. It also has four whip-like extensions on its body used to balance itself. The lungfish can actually drown, unlike most fish. It needs to breathe air. This means it can survive on land (sort of). If its water source dries up, it digs a hole and covers itself up in mucus, and then when the water comes back, it comes out. The lungfish is also a very old species. It has ancestry dating back four hundred million years. The cool thing is it hasn’t changed much in the long time span. Apparently the animal was very successful and had no reason to evolve.
The lungfish is a very primitive animal compared to some other animals whose ancestry has not been around as long. The lungfish is a vertebrate, which means it has a spine and a brain case. It is also a gnathostome, meaning it has a jaw. You would think this extremely old species could evolve some new advanced trait, but I guess it didn’t need to. Compared to some of the other animals on our cladogram, its life story is not all that long.
The lungfish is most closely related to all of the animals on the cladogram from the salamander to the Irish elk. The most advanced, or most recently developed, trait that the lungfish shares with those animals is being gnathostomes. As mentioned prior, it means they have jaws. The most important different between those animals and the lungfish is that all of the other animals are tetrapods. This means that they all have four limbs. I used the cladogram to figure this out by tracing my finger down the line to the lungfish’s most recent branching point or node. Then I found the most recent node the other animals share that the lungfish doesn’t. This told me what the biggest difference between the other animals and the lungfish was-the trait of being a tetrapod.
Last updated April 7, 2007.