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Scientists Say The Asteroid That Killed The Dinosaurs Almost Wiped Us Out Too (theweek.com) 265

HughPickens.com writes: Conventional wisdom states that mammalian diversity emerged from the ashes of the Cretaceous/Tertiary mass extinction event, ultimately giving rise to our own humble species. But Joshua A. Krisch writes at This Week that the asteroid that decimated the dinosaurs also wiped out roughly 93 percent of all mammalian species. "Because mammals did so well after the extinction, we have tended to assume that it didn't hit them as hard," says Nick Longrich. "However our analysis shows that the mammals were hit harder than most groups of animals, such as lizards, turtles, crocodilians, but they proved to be far more adaptable in the aftermath." Mammals survived, multiplied, and ultimately gave rise to human beings. So what was the great secret that our possum-like ancestors knew that dinosaurs did not? One answer is that early mammals were small enough to survive on insects and dying plants, while large dinosaurs and reptiles required a vast diet of leafy greens and healthy prey that simply weren't available in the lean years, post-impact. So brontosauruses starved to death while prehistoric possums filled their far smaller and less discerning bellies. "Even if large herbivorous dinosaurs had managed to survive the initial meteor strike, they would have had nothing to eat," says Russ Graham, "because most of the earth's above-ground plant material had been destroyed." Other studies have suggested that mammals survived by burrowing underground or living near the water, where they would have been somewhat shielded from the intense heatwaves, post-impact. Studies also suggest that mammals may have been better spread-out around the globe, and so had the freedom to recover independently and evolve with greater diversity. "After this extinction event, there was an explosion of diversity, and it was driven by having different evolutionary experiments going on simultaneously in different locations," Longrich says. "This may have helped drive the recovery. With so many different species evolving in different directions in different parts of the world, evolution was more likely to stumble across new evolutionary paths."
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Scientists Say The Asteroid That Killed The Dinosaurs Almost Wiped Us Out Too

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  • by Anonymous Coward

    That is totally not how things went down. [dinosaurusrex.ca]

  • by Anonymous Coward on Wednesday June 29, 2016 @11:50PM (#52417509)

    We got off the ark?

    • by agm ( 467017 )

      Hah! No-one is gullible enough to still believe such nonsense are they?

      • by Anonymous Coward on Thursday June 30, 2016 @12:06AM (#52417553)

        At least half of the American voters do! Why are you insulting them?!

        • Re: (Score:3, Informative)

          by agm ( 467017 )

          I'm not ridiculing individuals, I'm ridiculing patently absurd ideas. Ridiculous ideas deserve to be ridiculed. People should feel an intellectual shame in believing in goblins, fairies and gods.

        • Re: (Score:3, Insightful)

          by Opportunist ( 166417 )

          Because having imaginary friends is cute if you're under 8, after that it gets kinda sad, and when you pass 20 it gets scary.

          • by RabidReindeer ( 2625839 ) on Thursday June 30, 2016 @05:13AM (#52418069)

            Because having imaginary friends is cute if you're under 8, after that it gets kinda sad, and when you pass 20 it gets scary.

            When it gets really scary is when you pass it on to your kids.

            "Tommy, your great-great-...-great grandparents screwed up. So an all-powerful being says that that means that you deserve to die and then be roasted forever in pain. But don't be afraid. Just ask Jesus and he'll make it all better. He got himself killed painfully just to save you from that. And didn't even bother to ask permission from you first."

      • I have facebook contacts that seriously promote a flat earth...

      • Hah! No-one is gullible enough to still believe such nonsense are they?

        The B-Ark [everything2.com] seems unlikely to you?

      • Saw an ad for this on TV the other day:

        https://arkencounter.com/ [arkencounter.com] ...and was like wtf?!

        Boggles the mind.

      • Hah! No-one is gullible enough to still believe such nonsense are they?

        If I had a time machine, I'd go back and bitchslap that punk bastard Noah for bringing mosquitos and ticks on the ark.

        Also, I'd like to see all of the animals like the kangaroos, as they finished swimming the thousands of miles across the Indian ocean to the middle east so they wouldn't drown in the flood.

        But sad to say, there are indeed people that believe that there was a flood that covered the entire world, at least up to the level of Everest for a short time. Aside from the questions of where did the

        • To be fair, the ticks could have tagged along on the animals just fine. And stagnant water on the deck or in storage could have harbored plenty of mosquito larvae.

          What a global flood has to do with the meteor extinction event, I don't know. I know people like to inject off-topic jabs at religion every time dinosaurs are mentioned, but it's tired and not even funny here.

        • I would think that when the Mantle went Boom basically the entire world had around of WILL IT BLEND!!
          you can't really say that This Mountain was in place PreFlood.

          Gen 7:11
          "11 In the six hundredth year of Noah's life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened."

          https://answersingenesis.org/t... [answersingenesis.org]

          but yeah Meteor or Flood i would bet that 90% of the species (hint "kind" is not species) g

      • Diverse peoples from all over the world, some with no contact that can be described historically, share a similar myth of a great deluge. Call it nonsense if you want. I prefer to perceive a grain of truth, like the sand at the center of a pearl, encased in cultural and religious nacre, accumulated over millennia.

  • by mykepredko ( 40154 ) on Wednesday June 29, 2016 @11:52PM (#52417517) Homepage

    I always imagined that dinosaurs, as part of an ecosystem, were fairly well adapted to their environment. After the "extinction event", which significantly changed the environment and lead to their extinction would also result in the elimination of many species (both flora and fauna).

    What I found interesting that is hinted at in the TFA (and had not thought about) was the creation/availability of niches for surviving species to take over and evolve into.

    I would be quite interested in finding out if there are any fossil remains of mammals and how they fit into the ecosystem with dinosaurs before the big one hit. Other than cockroaches, I suspect that the Earth's inhabitants were wildly different and the different creatures inhabited different parts of the food chain would be very different from the ones that inhabited it after the meteor strike.

    Hopefully this research will result in more study being taken in the world of 60+ million years ago.

    • Re: (Score:3, Informative)

      by ITRambo ( 1467509 )
      Today's birds are what remains of dinosaurs, at lest the ones with wings that could get to safer ground, or air. The big dinos bit the dust. We came from very nimble and intelligent creatures that grew up and got even smarter, while removing the competition for food. Yeah, we kind of knew this.
    • by silentcoder ( 1241496 ) on Thursday June 30, 2016 @07:05AM (#52418221)

      >I would be quite interested in finding out if there are any fossil remains of mammals and how they fit into the ecosystem with dinosaurs before the big one hit

      There are, plenty. The oldest mammal fossils are between 150 and 200 millions years old. Mammals and Dinosaurs coexisted for a very long time. We identify early mammals by their teeth. Mammals alone have precisely interlocking teeth. This came at a price. Sharks and crocodiles can replace lost teeth indefinitely - but when you have precisely interlocking teeth every tooth is a snowflake, and so you can't just sausage-factory out infinite replacements. Mammals therefore only have two sets of teeth - one smaller set that sees them through childhood and a larger set through adulthood. All our dental issues and root cannals began with that.

      But it has a catch - to make the first set last through childhood, it had to be bigger than what can fit infancy - so for the first part of their lives mammal babies have no teeth at all. So they needed a new food source for babies. Thus was evolved: milk.

      So the teeth are a key clue to whether or not a creature was milk-producing, and it's how we differentiate early mammals from their reptilian contemporaries and close ancestors. The reason the date-span is so long (150-200 million) is that the oldest likely mammal fossil we have is 200-million years old, but many paleontologists believe it should be considered a reptile ancestor of mammals and not a true mammal yet. By 150-milliion years ago though, there were plenty of mammals and they were definitely mammals. These first definite mammals were morganucodontids which were tiny creatures that looked rather like shrews. They probably at seeds and the occasional dinosaur egg and were likely eaten by the smaller predatory dinosaurs in turn. They were however, brainy little guys. Their skull cavity for body mass ratio was far higher than any known dinosaur. They were our ancestors - and the mammalian trait of intelligence was already established.

        By the time of the K/T event they had diversified significantly into a number of species. What the study now actually says is that most of those species did not survive K/T - only a small number here and there made it through. And then, as plantlife recovered, there were these massive ecosystem niches ready to be taken advantage off - and no big creatures in the way, and those mammals were perfectly poised to take advantage. You often find the greatest diversity right after mass extinctions. With so many creatures gone, for a while almost any body plan can offer a workable survival advantage - and then as they start to compet with each other, it narrows down again into the winning categories.

  • Decimated means to kill 1 in 10.
    The author is not a very good writer. I believe the word he was looking for is annihilated.
    This is science. What words mean is important.
    • by hcs_$reboot ( 1536101 ) on Thursday June 30, 2016 @12:33AM (#52417595)
      Another (main) meaning of "decimate" is "kill, destroy, or remove a large percentage or part of". Who knows exactly how much time it took to eliminate the last dinosaur after the asteroid impact?
    • by dbIII ( 701233 )
      The beige box is now the "hard drive". To the Romans decimate was killing one in ten, to journalists today it means killing a lot more than one in ten.
    • According to the Oxford English dictionary, decimate meaning to kill 1/10 is something of an urban legend. You can read it for yourself here.

      http://blog.oxforddictionaries... [oxforddictionaries.com]
    • So, the word should technically be novemate? Novem is latin for 9...but I'm pretty sure novemate isn't a "real word" in any language lol.
    • FINALLY!

      While we're at pet peeves, don't call big changes "quantum leaps" either. A quantum leap is literally the smallest distance you could possibly move.

    • Decimated means to kill 1 in 10.

      In Latin, not so much in English. Yes, in English if the context is discipline in the Roman Legion, otherwise, 1 in 10 is a historical anachronism not a primary definition.

      The author is not a very good writer. I believe the word he was looking for is annihilated. This is science. What words mean is important.

      As politicians should leave science to the scientists, so should scientists leave the English language to the English major types and not try to misapply their love of metric prefixes like "deci". :-)

    • by quenda ( 644621 )

      Decimated means to kill 1 in 10. What words mean is important.

      What a travesty! Ironically, it begs the question, why are we disinterested?

    • by 140Mandak262Jamuna ( 970587 ) on Thursday June 30, 2016 @07:34AM (#52418269) Journal
      SI units are clear, decimate is to kill 10%. centimate is kill 1 in 100, millimate is 1 in 1000. Since the SI units go up or down by factor 10, the extinction event is actually 9.3 decimates.
    • European animals were decimated, american ones were inchimated.

    • Decimated means to kill 1 in 10.

      That's what it originally meant. If you knew how to internet, you could figure out that it now has other meanings.

      This is science. What words mean is important.

      And yet here you are, still ignorant of how to use a dictionary. I guess you don't have to feel very bad about that; An absolute shit-ton of Slashdotters have not figured that one out. You should probably refrain from telling other people what words mean, though, until you do.

    • by sootman ( 158191 )

      Sigh. http://blog.oxforddictionaries... [oxforddictionaries.com]

      "But the claim that decimate should be used to mean naught but to 'put to death (or destroy) one of every ten' has deeper problems than that. For it is not at all clear that this punitive sense is indeed the earliest definition of the word...

      "So given that these two meanings of decimate appeared almost simultaneously, why are we so obsessed with assigning the punitive meaning to the word? A likely answer is that people are falling prey to what is known as the Etymologi

  • It's been a long time since I studied any paleontology. Has the status of the brontosaurus gone from 'Whoops, never existed!' to 'Double whoops! Turns out it did!'?

  • Scientists Say The Asteroid That Killed The Dinosaurs Almost Wiped Us Out Too

    Heh. I had this picture in my head of a caveman riding on the back of a be-saddled T-Rex looking at a huge flash of light in the distance going: "What the fuck was that?!"

  • by Tablizer ( 95088 ) on Thursday June 30, 2016 @02:21AM (#52417779) Journal

    Just before the Permian-Triassic extinction event (PT), about 250m years ago, large mammal-like reptiles (proto-mammals) were more common than lizard-like reptiles. The proto-mammals were the top of the food-chain.

    But after PT, the lizard-like reptiles recovered faster, becoming the dinosaurs, and the proto-mammals were mostly small skittish creatures.

    The Cretaceous-Paleogene extinction event* (CP), the one that ended the dino's about 65m years ago, was pretty much the reverse: the lizard-ish reptiles recovered slower than the mammals.

    There was a short period early in the CP recovery where large dinosaur-like birds, think ostrich on steroids, seemed to have had the upper hand. (Birds are closely related to the dino's.) But, mammals eventually prevailed, as least as the largest beasts.

    If Trump gets us nuked [twimg.com], large dino/birds/lizards may make a comeback. If the pattern continues, it's their turn again.

    * Also known as Cretaceous-Tertiary extinction event

  • Why use a opossum as a size indicator? They are a marsupial, not a mammal like ourselves. An opossum is about the same size as a standard house cat, and a cat is a mammal, same as a human. And very possibly more familiar to folks outside North America.

    Only thing I can think is it gives some credence to that link, showing that the opossum's existence is due to the same event that lead to the proto-mammal that later split into simians and felids. Still would have made more sense to a banana.

  • Am I alone in hating this opening? It's as if scientists are a different species, or have a different way of thinking than the ordinary person. I look up to people who demonstrate a better understanding or a more reasoned view of the perspective. However, being a technologist and engineer, I find myself in parallel with the ideas presented. I feel as if I'm expected to observe myself through a microscope in a petri dish.

I've finally learned what "upward compatible" means. It means we get to keep all our old mistakes. -- Dennie van Tassel