Marsupial evolution

wolf vs. dog, lateral (both placentals)

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wolf vs. thylacine, lateral (placental vs. marsupial)

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wolf vs. dog, anterior (both placentals)

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wolf vs. thylacine, anterior (placental vs. marsupial)

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wolf vs. dog vs. thylacine, ventral (two placentals vs. one marsupial)

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wolf vs. dog vs. thylacine, lower jaw (two placentals vs. one marsupial

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kangaroo vs. thylacine, lateral. (both marsupials)

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possum vs. thylacine, lateral. (both marsupials)

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kangaroo, possum, thylacine, anterior. (three marsupials)

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kangaroo, possum, thylacine, ventral (three marsupials)

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kangaroo, possum, thylacine, lower jaw (three marsupials)yes. marsupials ARE more similar to each other than to their similar-looking placental counterpart. it might not be obvious from tiny pictures of the living animal, but the internal anatomy is a dead give-away.Edited by arachnophilia, : found jpgs. slides used by kevin padian during the kitzmiller v. dover trial, courtesy of the national center for science education. (used without permission, under fair use, sorry about the bandwidth)Edited by arachnophilia, : wrong picture

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thank you, i typoed on the filename in the img tag. it has been fixed.

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evolutionary biologists can easily tell, yes. oh, that's cheating. the ventral views with the palatial holes are a dead give away! if it's got them, it's marsupial. that's a rather easy rule to remember. the fact that students fails tests has no bearing on the facts. in fact, they fail because they get the facts wrong. i've failed a paleo test before too, you know. heck, my professor didn't even mark me down when i mixed up a dalmanites with a ptychopariid trilobite (cause my drawing of the geesops one ROCKED). does that mean a qualified paleontologist can't tell the difference between a dalmanites and a ptychopariid? heck no. of course they can. they look similar to the untrained eye, but that's why it's called "the untrained eye."people who specialize in things know more than your average student, or ignorant bystander. but the bystander's ignorance is not the fact -- the expert's knowledge is. and those palatial holes and dental forumalae ARE significant. feel free to compare to the above. i see 2 molars, 4 premolars, and a carnassial tooth on top, 3 molars and 4 premolars on the bottom. i see no palatial holes. lacrimal bone visible from side. the joint between the upper and lower jaws looks like a placental one. i see pinched nasals. the cheek bone's suture looks like a placental one.the whole, it looks a lot like the dog of the wolf, but NOT the tasmanian "wolf" that looks more like the kangaroo. sorry, you're still wrong. try again. if by "strikingly" you mean "not at all." yes, the platypus was clearly sewn together as a joke amongst biologists. haha funny stuff that. cats have stripes too. lots of things have stripes. coloration patterns come and go very quickly evolutionarily speaking. look at all the different breeds of dogs -- all the same species. how an animal is colored is actually irrelevent. things like osteology (as above) are much, much more important. maybe not as obvious to someone who doesn't know anything about biology, but important nonetheless.

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nosy, it's a superficial difference: the kind of things creationists bring up saying "look at this marsupial that looks like a placental," as contrasted with the more important skeletal and genetic differences. it certainly seems on-topic, as the topic is "looks similar" vs. "is related."

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no, they don't. the thylacine skull and body plan may look vaguely dog-like to you, but it's not any closer to a dog than a kangaroo is. both come from smaller marsupials that you'd mix up with placental rodents. it's simply convergence, and we know it's convergence because the details are more similar to other marsupials than to placentals. of course. they're still mammals, which means they're still therapsids. the evolutionary tree is organized (partly) on the basis of apomorphy and plesiomorphy. since the features that group a thylacine together with a dog are much more basal general features, their common ancestor is lower on the tree. whereas the features that goup it together with a kangaroo are very specific, and so they divide higher on the tree. marsupials (metatheria) aren't really an anomaly. they are a half-way point between laying eggs (monotrema) and full live birth (eutheria).Edited by arachnophilia, : typo

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