Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Tuesday, August 15, 2017

Hey, Rocky! Watch me pull a rabbit out of a hat!

Because so much of the world lately seems to be immersed in hatred, violence, and just general suckiness, for today I'm going to retreat to my Happy Place, which is: cool scientific discoveries.

Today's contribution from the Happy Place comes from the fields of paleontology and evolutionary biology, two disciplines that are near and dear to my heart.  While my educational background is kind of all over the map (less charitable sorts have called it "a light year across and an inch deep"), evolutionary biology has been something of a passion of mine for ages.  In getting my teaching certificate, I did as many courses as I could that focused on such things as population genetics, cladistics, and the origins of life, so I have come to think of that as being more or less my specialty within the field.

The discovery that spurred today's post comes from northeastern China, where two new species of mammal were uncovered (literally and figuratively) -- Maiopatagium and Vilevolodon.  These species were probably closely related, and appear to have been small tree-dwellers who had flaps of skin that ran from the outsides of the front legs to the outsides of the hind legs, so that when necessary, they could jump from a tree branch, fling their limbs outward, and glide like a living kite.

[image courtesy of study leader Zhe-Xi Luo of the University of Chicago]

If you're thinking, "Wait a second.  Isn't that just a flying squirrel?", you should know two things: (1) these two species were only very distantly related to flying squirrels and other rodents; and (2) they were alive during the Jurassic Period -- something on the order of 160 million years ago, when the dominant life forms were dinosaurs.  (For comparison purposes, the earliest known rodents didn't show up until 100 million years later.)  They belong to a group called Euharamiyids, one of the four branches of true mammals (the other three are the Multituberculates, which like the Euharamiyids are extinct; the Monotremes, which include egg-laying mammals such as the platypus; and the Therians, which encompass all other mammals, including us).

What I think is coolest about all of this -- besides the fact that ancient animals are simply inherently cool -- is that it's further evidence of the fact that similar selective pressures often result in separate lineages that happen upon the same "solutions" to evolutionary problems.  This is called convergent or parallel evolution, and one of the best examples of this is the evolution of flight and/or gliding.  Taking to the air has apparently evolved over and over again, resulting in the most familiar flying groups -- birds, insects, and bats -- but also in...



Flying fish:

Sugar gliders:

and the aforementioned flying squirrels:

... the latter of which were studied extensively by noted scientists Boris Badinov and Natasha Fatale.

And now, we can add two more to the list, a pair which (like all the rest) evolved aerobatics completely independently of all the others.

Anyhow, the whole thing illustrates a fundamental rule of biology, which is that there are a limited number of powerful evolutionary drivers (the most important being finding food, not getting turned into food, avoiding the vagaries of the environment you're in, and finding a mate), and a limited number of solutions to those drivers in the real world.  So it's inevitable that the same kinds of structures and behaviors will evolve over and over, even in groups that aren't very closely related.  What is most remarkable about this particular discovery, however, is how early the innovation of gliding in mammals evolved -- back when the whole mammalian clade had barely gotten started, and the dinosaurs still had 95 million years left before a giant meteor strike ended their hegemony.

And all of this ties into another field I'm fascinated with, which is exobiology -- the study of alien species.  At the moment, the number of available samples to study is zero, so we're left speculating based on what we have here on our home planet.  But the fact that we see the same sorts of patterns cropping up again and again -- bilateral symmetry, organs for sensing light and sound, defensive and offensive weapons, and adaptations for rapid locomotion -- is a pretty sound argument that when we do come across life on other planets, it will probably have some striking similarities to what we see here on Earth.

So that's our cool scientific discovery of the day, courtesy of a research team working in China.  And unfortunately I need to wrap up this post, which means I have to leave my Scientific Happy Place and return to the real world, at least for a little while.  Maybe I'll luck out and there'll be other fun and fascinating discoveries announced soon so that I can read something other than the news, which is more and more making me wonder if it might not be time for another giant meteor to press "reset" on the whole shebang.

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