- Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms generally vary along geographic gradients of latitude, elevation, isolation and habitat. Incorporating the theory of plate tectonics and fossil evidence helps explain both similar and dissimilar flora and fauna.
- Biogeography helps explain why penguins are found in the Antarctic and polar bears are found in the Arctic. But what explains this emperor penguin decoy rover?!
This National Geographic article about sending in penguin rovers describes the lower stress the penguins exhibit at having a cute penguin rover rather than a human collect data.
Back to biogeography: the location of penguins in the southern hemisphere is correlated with those areas being connected through geologic time:
Likewise, polar bears' habitats in the northern hemisphere are correlated with areas which were once or are currently connected tectonically.
The location of the continents as one super landmass known as Pangaea up until about 200 my ago is illustrated here:
Then, about 200 million years ago, Laurasia drifted northward from Gondwanaland (surely you've seen "Reunite Gondwanaland!" tee-shirts):
Polar bears' decline by almost 50 percent in research presented this week doesn't include rolling or swimming polar bear rovers. It does show alarming drops in the polar bear population due to thinning sea ice and concomitant inability to hunt for seals, a key part of their diet.
This article from Brown University ties together clade and cladograms and Biogeography.
Still scratching my head about alligator distribution in the southeastern U.S. and easternmost China (as discussed briefly last week). The time frame of alligator distribution only from Pleistocene to Recent likely explains part of it. But part is still a mystery.
Red rover, red rover, let the alligators come over and explain their distribution.
Biogeographically,
Steph
P.S. My friend, Cat, so adores penguins her personal email address includes gentoo. She and I were in the same plate tectonics class senior year at Smith so we go back tectonically as well as penguinally. Cat, this one is for you!
The transformation gets me every time. . .
Steph,
ReplyDeleteFirst, a serious question. Were/(are?) the continents of Antarctica, Australia, Africa and South America (ever) connected tectonically?
A few perhaps “numb” questions: Are penguins good swimmers over long distances? If they are, does/did this have any bearing (Strait!) on whether continental land masses are connected. There is no way penguins or polar bears could migrate from pole to pole, right? Even over generations?
I wonder how those penguins would react if Rover, my Great Dane, were collecting data on them. When it comes to Great Danes, Caveat Emperor!
When will you tackle the subject of Geoautobiography, the story of the short-lived Geo Metro (1989-2001)?,
LegoSubCompact
Lego, I will start with the paleogeography. Absolutely, most geologists believe all the continents were connected as Pangaea up until about 200 million years ago. Then, the northern landmass of Laurasia drifted north from the more southerly Gondwanaland. I will post some illustrations above.
DeletePenguins are good swimmers. Most swim 4-7 mph although the gentoo penguin has been clocked at 22 mph in the water (Whoa! I am not a super fast swimmer but reasonably fast and I swim just 2 miles in an hour).
DeleteAs to moving pole to pole, the environments at the north and south poles are so different (sea ice vs landmass), that if a stray penguin swam that far north (unlikely), it would not survive long and might be eaten by a polar bear (It's an acquired taste).
Lego, a little Fleetwood Mac in the morning was a great start to the day.
DeleteNot sure about the geoautobiography but it would be fun to share our first vehicles. Mine was a 1979 tan VW Rabbit, purchased in Dallas, TX. Loaded everything I owned in that car to drive from Dallas to Denver!
I inherited a '62 Bonneville from my uncle -- it had been stolen, replaced, and then recovered, sans wheels and battery. Burned a quart of oil a week, until I left it at home when I went off to college, and my father forgot about the oil. My first car was a '71 Corolla, which I loved despite the fact that, because the ignition coil was mounted to the front grill, every time I drove in the rain it would go slower and slower until it died and I pulled over, opened the hood, and dried off the wires.
Delete...Oh, and that '71 Corolla took me and all my worldly possessions from Long Island to Miami, FL (and back, after I switched grad schools).
DeleteAnd we never worried if they'd make the trip(s)!
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ReplyDeleteLMAO at the Le MAhO rover pix. Looks like a cute set of wheels is a real chick magnet, as we've long suspected.
ReplyDeleteHahahaha!
DeleteWhatever you do, keep those penguins away from the fur seals!
DeleteIt's a little creepy no matter why the fur seals are doing it.
DeleteI am happy to know there's a Polar BiologyJournal, though.
Oh, it's more than a little creepy. What's worse, it reminds me of a really bad joke involving a penguin and a seal, which you shouldn't Google if easily offended.
DeleteHmmm, headed over at noon for the kindergarten Thanksgiving feast. But, I don't think I will be sharing that joke amongst the pilgrims and Indians and squash.
DeleteWe once discussed living fossils here. I thought PEOTSers might appreciate this short appreciation of the Ginko by everyone's favorite neurologist.
ReplyDeleteThanks, jan, that was beautifully written. I am such a fan. A new mystery to ponder today.
DeleteGinkgo is the classic plant fossil paleontologists point to as having appeared all over Gondwanaland up until the late Triassic, around 200 my ago.
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DeleteYour picture of polar bears above reminded me of a terrific book I read last year, Grizzlyville, by Jake MacDonald. Despite the name, he talks about polar bears and black bears, too. OK, I admit I'm a fan of bears, but I think this little book is worthwhile, anyway.
ReplyDeleteGrizzylyville looks great, jan.
DeleteThe ultimate polar opposites: polar bears and penguins.
Have we ever discussed what wiped out the dinosaurs?
ReplyDeleteWe could start with a legit source which includes my personal favorite, paläoweltschmertz, German for just getting worn out.
DeleteOr go with the Alvarezes, asteroids, climate-changing, mammal egg-eating hypotheses.
Maybe they saw the asteroid coming, ate some phenobarbital-laced applesauce, tied plastic bags over their heads, and rendezvoused with the Mother Ship.
DeleteSeriously, on page 3 I read:
The asteroid would have hit with the force of 100,000 billion tons of TNT. This would have generated an earthquake one thousand times greater than the largest ever recorded, with winds of over 400 kph.
And then on page 4:
Although the impact hypothesis is the most widely accepted explanation of the K/T extinction, other theories still remain. Evidence of widespread volcanism, particularly at the Deccan traps in India, correlates with this moment in time as well. Prolonged volcanism could have led to atmospheric and climatic changes similar to those proposed for an asteroid impact.
As the nincompoop said to the geologist:
"Could prolonged, widespread volcanism be a consequence of a ginormous earthquake?"
A little bit of onion goes a long way in a humongous omelet.
Why does spellchecker dislike 'volcanism'?
We've probably been over this ground before, but why is Cretaceous/Tertiary abbreviated K/T? I'm gravitating toward </T.
Dichiselously,
Who Else?
Cretaceous is K for German Kreide (chalk) because C is for Carboniferous. And T is for Paleogene, of course. Because Tertiary is such a third-rate name. Period.
DeleteAnd nincompoop is such an etymologically tasty word, going back over 300 years (nearly to the K/T boundary!), from non compos mentis. You'd have to be out of your mind not to love it!
DeleteYeah, we did talk about this, Paul...with the Alvarezes way back in 2013. That worldwide iridium layer was perfectly happy being called the K/T boundary, smiling along with the other Katies. Then the nomenclature committee decided we had to refer to the early Tertiary as Paleogene, causing a switch to K/P and all those kitchy kitchen duties.
DeleteNincompoop is a great word; I also like nincompoopery. Lots of "oop" words are fun: oop, poop, whoop, boop, sloop, hoop and many more. The "oop" sound is inherently funny (well, to me anyway).
And, Paul, to answer your excellent question, volcanism can be a consequence of large eathquakes. To wit: Which came first. . .?
DeleteMAPS, WE GOT MAPS. # 16, 17, and 20 were especially interesting to me.
ReplyDeleteI really like your last "transformation" picture. Sometimes a too-slow shutter is just what you need.
ReplyDeleteMy problem with whipping cream is knowing, in my enthusiasm, when to stop, to avoid going over the line to butter.
I found this handy little chart, which should take care of the more inquisitive kids in the class.
George Carlin and I ask, how do you know when sour cream's gone bad?
Thanks, jan. I really like the look on the shaker's face in that image. They were so excited waiting for the switch to a solid. I enjoyed your chart, too, and groaned at the GC joke. . .
DeleteMy wife passed me a link to this Wired essay by Marsha Ivins that I thought might be of interest, including a non-Ivins-related video that the kids may enjoy. Poking around on the web, I found this older Mother Jones piece on Ivins, including an audio-only interview (which starts 16.5 minutes in on the link on that page).
ReplyDeleteThe bubble video is great. I will show the kids.
DeletePoked around trying to see if Marsha Ivins and the late Molly Ivins are related (I don't think they are), but I did find this Molly Ivins piece invoking inveighing. Sure miss that Smithie's wit!
WHITE MATTER PLASTICITY STUDY AT BROWN UNIVERSITY!
ReplyDeleteBlack girls and STEM
ReplyDelete