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New "Last Dinosaur" Find Backs Asteroid Extinction

samzenpus posted more than 3 years ago | from the sky-is-falling dept.

Science 157

An anonymous reader writes "A new fossil discovery has suggested that dinosaurs were alive right up until the asteroid impact, and did not go extinct gradually due to climate change or changes in sea level, as previous theories have proposed."

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Nonsense! (5, Funny)

Anonymous Coward | more than 3 years ago | (#36753838)

They were killed by all of the cavemen for food.

At least that's what my science teacher told me.

- A Student from Kansas

Re:Nonsense! (1, Funny)

ckblackm (1137057) | more than 3 years ago | (#36753878)

Apparently you weren't paying attention. The Flying Spaghetti Monster put the bones out there for people to find, there weren't any dinosaurs as the world is only a few thousand years old!

Re:Nonsense! (0)

Anonymous Coward | more than 3 years ago | (#36754070)

Since you believe in the FSM, let my introduce you to my PHYS .... purple headed yogurt slinger

Re:Nonsense! (1, Funny)

dkleinsc (563838) | more than 3 years ago | (#36754218)

Aye, matey! Thar be the bones of dragons in the deeps. But which fell by His Noodlyness, and which by me blunderbuss?

Re:Nonsense! (1)

qzjul (944600) | more than 3 years ago | (#36754692)

I believe you're mistaken; the world was created Last Thursday, with all the apparent trappings of a world much older!

Last Thursdayism [wikipedia.org]

Re:Nonsense! (1)

TheABomb (180342) | more than 3 years ago | (#36755966)

That explains things. I never could quite get the hang of Thursdays.

Re:Nonsense! (4, Funny)

CajunArson (465943) | more than 3 years ago | (#36754020)

You religious wingnut! Everyone knows the Dinosaurs went extinct because climate change caused by the the Bush Tax Cuts and Big Oil!

        - A Student from San Francisco

Re:Nonsense! (1)

UnknowingFool (672806) | more than 3 years ago | (#36754112)

I have it on good author-it-ay that Obamacare is responsible.

Re:Nonsense! (3, Interesting)

Normal Dan (1053064) | more than 3 years ago | (#36754194)

I blame our next president.

Re:Nonsense! (2)

GooberToo (74388) | more than 3 years ago | (#36754984)

I have it on good author-it-ay that Obamacare is responsible.

I just KNEW those death panels had something to do with something. Dinosaur extinction it is!

No public option! (0)

Anonymous Coward | more than 3 years ago | (#36755954)

That's because mister "We need a public option", Liberman, suddenly changed his mind and made sure there wasn't one.

Re:Nonsense! (3, Insightful)

mswhippingboy (754599) | more than 3 years ago | (#36754696)

You religious wingnut! Everyone knows the Middle Class went extinct because of the the Bush Tax Cuts and Big Oil!

- A Student from San Francisco

There. FTFY.

Re:Nonsense! (0)

Anonymous Coward | more than 3 years ago | (#36755424)

These are about as good as the earlier posts this morning with Bill Gates vs Steve Jobs using their respective "sent from my [iphone, windows 7 phone]" messages.

I find these amusing as well. Shall we call this signature based humor?

Ah, but HOW? (0)

overshoot (39700) | more than 3 years ago | (#36754130)

They were killed by all of the cavemen for food.

Mine taught us that they were ridden to death.

Re:Ah, but HOW? (-1)

Anonymous Coward | more than 3 years ago | (#36754374)

Poor Jesus Ponies.

Re:Nonsense! (0)

Anonymous Coward | more than 3 years ago | (#36754224)

I remember my father once telling me that his high school science teacher frequently told his students that "Dinosaurs never existed. god put [those] bones in the ground as a test of faith."

Historically, being a christian and trying to teach science objectively seems like kind of a conflict of interest.

Re:Nonsense! (1)

pnewhook (788591) | more than 3 years ago | (#36754826)

Christianity is not in conflict with evolution. Only crackpot fundamentalism is.

Re:Nonsense! (0)

tverbeek (457094) | more than 3 years ago | (#36754346)

That's absurd. They died in The Flood, an "extinction event" that lasted 40 days and 40 nights. How else do you think all those dinosaur bones got buried in the sediment?

Re:Nonsense! (1)

SleazyRidr (1563649) | more than 3 years ago | (#36754506)

What about the dinosaurs that lived in the water?

Re:Nonsense! (1)

gstrickler (920733) | more than 3 years ago | (#36754684)

It rained 1 day of "heavy water" which killed the water dwellers, followed by 39 days of "light water" which drowned everything else. Then, about 99% of the heavy water miraculously disappeared (or changed into light water) leaving us with the current 3600:1 light/heavy ratio.

Re:Nonsense! (4, Interesting)

alexo (9335) | more than 3 years ago | (#36755036)

It rained 1 day of "heavy water" which killed the water dwellers, followed by 39 days of "light water" which drowned everything else. Then, about 99% of the heavy water miraculously disappeared (or changed into light water) leaving us with the current 3600:1 light/heavy ratio.

Close, but not quite.

It actually rained super-heavy water (Tritium Oxide) and not "plain" heavy water (Deuterium Oxide), which killed the water-dwelling dinosaurs via internal beta emission. while being largely ineffective against land-dwelling creatures due to its short biological half-life (7-14 days).

Also, need for miraculous disappearance since, while Deuterium is stable, Tritium has a half-life of about 4,500 days.

Science. It works, bitches!

Re:Nonsense! (2, Funny)

DocHoncho (1198543) | more than 3 years ago | (#36755572)

So THAT'S why the instructions for the Ark included two hands of lead shielding!

Re:Nonsense! (1)

SleazyRidr (1563649) | more than 3 years ago | (#36755850)

That was an awesome explanation. Almost awesome enough to make me want to convert.

Re:Nonsense! (1)

alexo (9335) | more than 3 years ago | (#36755956)

That was an awesome explanation. Almost awesome enough to make me want to convert.

Note to self: next time add smileys.

Re:Nonsense! (0)

Anonymous Coward | more than 3 years ago | (#36754686)

They also drowned

Re:Nonsense! (1)

JustOK (667959) | more than 3 years ago | (#36754970)

They died when it dried up.

Re:Nonsense! (0)

Anonymous Coward | more than 3 years ago | (#36754718)

The dinosaurs died out exactly 65,000,027 years ago. I just checked my notes from high school.

Re:Nonsense! (0)

zorca (954500) | more than 3 years ago | (#36754860)

clearly, dinosaurs didn't fit on the ark!

What sort of rock was it found in? (1)

Anonymous Coward | more than 3 years ago | (#36753852)

What sort of deposit was the horn found in? If there were enough water, isn't it possible that the horn could have been displaced and thus ended up in younger sediments? My university coursebook says that that is oft to occur with dinosaur teeth; could similar happen with a dinosaur's horn?

Re:What sort of rock was it found in? (0)

Anonymous Coward | more than 3 years ago | (#36754656)

In the original paper, there are good reasons to think it was not reworked. .

Re:What sort of rock was it found in? (2)

Paltin (983254) | more than 3 years ago | (#36754954)

Hell Creek formation = fluvial (river) deposits.

Reworking is always a possibility.

This specific fossil is claimed to have been found in an overbank deposit, which means that it was out on the flood plain, which if true means it is unlikely to have been reworked. But I'd want to see it for myself.

Oh no (-1, Offtopic)

serkit (2358056) | more than 3 years ago | (#36753856)

Is that some first post?

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Re:Oh no (1, Insightful)

harrytuttle777 (1720146) | more than 3 years ago | (#36755032)

Typical assholes. You can't be black or gay here. You get mooded down by the hyper elit global warmining believing jerks. I go from great karma to terrible karma in 2 hours for posting a comment questioning global warming. You will probably get the same treatment by the mods for being a gay nigger. Sorry. I feel your pain.

Without proof to the contrary... (1)

JamesonLewis3rd (1035172) | more than 3 years ago | (#36753916)

...I assert that dinosaurs did not growl or make any other scary sounds...they mooed.

Re:Without proof to the contrary... (0)

Anonymous Coward | more than 3 years ago | (#36754042)

Depends on what you watch. A moo can be scary [youtube.com] .

Re:Without proof to the contrary... (0)

Anonymous Coward | more than 3 years ago | (#36754104)

...I assert that dinosaurs did not growl or make any other scary sounds...they mooed.

Nah, they chirped and sang like they do today.

Re:Without proof to the contrary... (1)

gestalt_n_pepper (991155) | more than 3 years ago | (#36754212)

Nonsense. They sang show tunes and were summarily executed by all other animals after one too many renditions of "Oklahoma."

Re:Without proof to the contrary... (0)

gstrickler (920733) | more than 3 years ago | (#36754622)

+1, Sorry, no mod points today.

Mooing ostriches (1)

tepples (727027) | more than 3 years ago | (#36754214)

...I assert that dinosaurs did not growl or make any other scary sounds...they mooed.

"Mooing" isn't actually far off the mark, given videos like this [youtube.com] and this [youtube.com] . One might imagine that this antediluvian bird [wikipedia.org] (pictured: a modern reconstruction of the raptor Deinonychus) might have made similar sounds.

Re:Without proof to the contrary... (0)

Anonymous Coward | more than 3 years ago | (#36754548)

No, they were mimes. Explains how they died too.

Re:Without proof to the contrary... (0)

Anonymous Coward | more than 3 years ago | (#36754950)

And why nobody cared.

Re:Without proof to the contrary... (1)

garyebickford (222422) | more than 3 years ago | (#36757124)

Tyrannosaurus apparently has the bone structure of a big chicken. So I'm thinking it made VERY BIG clucking and crowing noises! :P
"COCK-A-DOODLE-DO, MF!!"

(old joke - Where does an 800 lb. canary sit? Any place it wants too!)

Scientific Method, Yay! (1)

bughunter (10093) | more than 3 years ago | (#36753918)

Good news: the Scientific Method is still alive.

The bad news: This pretty much disproves my hypothesis of Sauroflatulogenic Climate Change.

Re:Scientific Method, Yay! (1)

gestalt_n_pepper (991155) | more than 3 years ago | (#36754238)

Why, pshaw! How do you think the atmosphere ignited when the meteors hit?

Re:Scientific Method, Yay! (0)

Anonymous Coward | more than 3 years ago | (#36756432)

Using this article as proof that "the scientific method is still alive" is a complete failure of the scientific method itself.

Re:Scientific Method, Yay! (1)

gstoddart (321705) | more than 3 years ago | (#36758186)

Sauroflatulogenic

Expialidocious? [wikipedia.org]

"Caused by the flatulence of sauropods" ... if that isn't real latin, then it's the best faux latin I've seen in a long time. And, if it is latin, bravo for knowing it.

SauroflatulogenicExpialidocious ... oh, that's just funny.

So it's not Denver? (1)

Hsien-Ko (1090623) | more than 3 years ago | (#36753952)

Because that was my favorite totally rad "Last Dinosaur".

Re:So it's not Denver? (1)

wootest (694923) | more than 3 years ago | (#36753992)

He's my friend and a whole lot more.

What a Concidence! (1)

psiXaos (702248) | more than 3 years ago | (#36754002)

Creepy concidence hre. I had just finished wathing "National Geographic Explorer: 24 Hours After Asteroid Impact" documentary seconds ago when I loaded slashdot to see this story. I recommend that documentary btw; it really dwarfed all my previous imagination of what might have occured...

Re:What a Concidence! (1)

ByteSlicer (735276) | more than 3 years ago | (#36754272)

Ah yes, what are the chances of some random nerd seeing a documentary about something that will turn up as a story on /.
Given enough nerds, actually close to 100% ...

(Not to bash on you, but coincidence is often overrated)

You all have it wrong! (1)

Uhhhh oh ya! (1000660) | more than 3 years ago | (#36754044)

Dinosaurs became extinct because they had laser eyes and they killed each other. No one has yet been able to disprove this theory.

https://www.facebook.com/group.php?gid=19135208295 [facebook.com]

Re:You all have it wrong! (1)

SnarfQuest (469614) | more than 3 years ago | (#36755736)

They got in a fight with the laser mounted sharks, and killed each other off.

Real Killer (0)

Anonymous Coward | more than 3 years ago | (#36754050)

As I recall, all the dinosaurs were killed by a gigantic Brain in an attempt to memorize everything about the universe and then destroy it.

Re:Real Killer (1)

kannibal_klown (531544) | more than 3 years ago | (#36754116)

In an unrelated story: Beavers mate for life

Re:Real Killer (0)

Anonymous Coward | more than 3 years ago | (#36754326)

And then he left Earth for no raisin at all.

No, it doesn't (5, Informative)

Wyatt Earp (1029) | more than 3 years ago | (#36754076)

The margin of error on when the last dinosaurs were existent and the margin of error on when the K-T boundary was deposited are both hundreds of thousands of years.

In some places there are at least 300,000 years of sediment between the fossil evidence of the Cretaceous–Tertiary extinction event and the K-T boundary.

K-T boundary has is dated to (65.5 ± 0.3) Ma, the Cretaceous–Tertiary extinction event is dated to 65.5 Ma, so the impact could have been the day the last dinosaurs were alive, it could have been 300,000 years before, 11 years after, or 213,417 years after.

Re:No, it doesn't (3, Funny)

Anonymous Coward | more than 3 years ago | (#36754166)

You're right.

In fact, the truth is that the dinosaur extinction caused the asteroid impact event. Intelligent dinosaurs had maintained a force shield which protected the Earth, but after they died out (turned out that, unfortunately, the force shield was carcinogenic) and the shield went off-line, Earth was wide-open for a cataclysmic impact.

--Alastair

Re:No, it doesn't (2)

JustOK (667959) | more than 3 years ago | (#36755060)

Dino might!

Re:No, it doesn't (4, Insightful)

thoromyr (673646) | more than 3 years ago | (#36754352)

what I got from reading the article was that the author had a conclusion that wasn't supported by the evidence. Taking the finding at face value, a solitary find that is significantly closer than expected to the estimated time of impact would tend to support a gradual extinction. If the extinction were sudden, due to the asteroid impact, then a wealth of fossil data would be expected all the way up to the estimated time of impact, with very little (quickly going to none) following it. Instead there is (apparently, and this is information provided and agreed on by the article) a significant gap with -- to date -- a single fossil found in the region.

As far as I can tell it is another data point of no particular significance. To "disprove" gradual extinction before the impact a number of fossils representing normal population levels and distributions needs to be found.

Re:No, it doesn't (0)

Anonymous Coward | more than 3 years ago | (#36754802)

The idea that dinosaur fossils do not occur closer than 3 m from the contact has been disprove several times. As to the idea that dinosaurs are not found at the impact horizon--it would be very unlikely. In Wisconsin deer have lost their predators and are over abundant--far more abundant than dinosaurs would have been. Shoot and bullet across the state and the likely hood that any deer would be hit is very small. In outcrop the K-T boundary or any boundary is essentially a line. So the same applies. Large animals are simply very rare. Go in the woods and randomly look in one direction. Even if an animal is present within sight it is very unlikely it will be in your direct line of sight. The dinosaurs died over a broad landscape at the K-T impact. But what we see now is simply a line of outcrop through that landscape--very unlikely you would find a dinosaur.

Re:No, it doesn't (2)

Wyatt Earp (1029) | more than 3 years ago | (#36754916)

Dinosaur remains have been found as close a cm from the K-T layer and out to a meter, the 13cm distance in west Texas is 300,000 years of sediment.

Re:No, it doesn't (1)

egardner4 (652075) | more than 3 years ago | (#36757862)

Well said. That was exactly my first thought too.

Re:No, it doesn't (2)

Paltin (983254) | more than 3 years ago | (#36755024)

The thing is - if they were in fact concurrent - then we'd expect that as better data becomes available, the dates converge.

This is exactly what has happened over time. There's actually new work being done by Zircon workers that continues to close the gap.

And yes, this IS evidence that supports that dinosaurs went extinct at the boundary. It increases the possibility of that, to the exclusion of others possibilities, by at least a little bit.

Re:No, it doesn't (0)

Wyatt Earp (1029) | more than 3 years ago | (#36755194)

No it really doesn't Even if the gap is closed to 30,000 years, that is thousands of large vertebrate generations apart.

There are very few continuous beds of fossil-bearing rock which cover a time range from several million years before the K–T extinction to a few million years after it, so extinct large vertebrates could very well have become extinct millions of years before the K-T layer in some places and survived for millions of years after it.

The K-T boundary and the asteroid hypothesis as the one true theory is junk science for scientists who like to star in flashy TV programs about "Asteroids killed the Dinosaurs!"

Re:No, it doesn't (3, Insightful)

Paltin (983254) | more than 3 years ago | (#36755380)

But there isn't a -gap-. There is uncertainty as to the exact timing. A gap is a period when you are sure there isn't anything; uncertainty means you don't know. To the best of our knowledge - and constantly improving as more work is done - the uncertainty periods are getting smaller. This is evidence for concurrence. Concurrence is not disproven, and the evidence that supports it keeps getting better as it is refined.

There are no terrestrial beds of fossil bearing rock that also contain unequivocal markers of the K-T iridium spike. That's why we have correlation. There are lots of continuous beds of fossil bearing rock that do contain the K-T and show evidence of mass extinction - in the marine realm. Foram extinction and population is well documented and not disputed, as well as other marine creatures. The most likely explanation is that the impact had some role in the extinction.


|...as the one true theory....

The article doesn't claim anything about one true theory, and neither did I. Straw man at it's best. Scientists look for evidence and weigh it. I recommend you learn more about Bayes theorem and then reexamine the evidence.

K-T boundary is well defined (2)

mangu (126918) | more than 3 years ago | (#36756812)

K-T boundary has is dated to (65.5 ± 0.3) Ma, the Cretaceousâ"Tertiary extinction event is dated to 65.5 Ma, so the impact could have been the day the last dinosaurs were alive, it could have been 300,000 years before, 11 years after, or 213,417 years after.

You are assuming both calculations are independent, but they may not be. The asteroid collision threw up a lot of chemicals which characterize well the asteroid collision, among them an abundance of iridium.

You don't need to calculate the date exactly, if a fossil is in this iridium rich layer you can assume it died on the asteroid impact, that is both events happened on the same date even if you don't know exactly which date it was.

Wait a fricken' second. (2)

blair1q (305137) | more than 3 years ago | (#36754106)

They couldn't find any dinosaur bones within 3 meters of the boundary, then they found one 13 cm below the boundary, and they still claim the asteroid extincted them?

I want to see a bunch of bones lying on the boundary. Contemporaneous with the event. Show that the effect [extinction of dinosaurs] comes after the cause [asteroid that created the K-T boundary]. Until you can do that, you can't even associate the asteroid with the extinction. Even at 13 cm, they're not at all well-correlated.

Re:Wait a fricken' second. (0)

Anonymous Coward | more than 3 years ago | (#36754536)

It's not that easy. What if those 13 cm were mud at that time? Or some digging / earth movement happened.

But I agree, that if that was the case, there should be correlations for it, that can't be associated with anything else. (Aka. what dumb people call "proof"... something that doesn't exist in the scientific method [tinypic.com] , as it is nonsense.)

Re:Wait a fricken' second. (3, Informative)

Paltin (983254) | more than 3 years ago | (#36754706)

That's not how it works.

Considering the vast amount of time captured in even 13 cm of strata, there are many more generations of dinosaur corpses created and sorted through the taphonomic filter than would be created by a sudden extinction event. The deposition associated with the Hell Creek is one of rivers - which means there's a lot of energy to destroy things, as well as problems transporting from death location into the river to begin with. Simply put, there is no reason to expect that you'd fine a single bone from the last generation of dinosaurs - and even if you did, you'd have a hell of a time proving it.

Here's an example paper from the modern that looks at this problem : http://www.cornellcollege.edu/geology/greenstein/personal/Reprints/Diadema.pdf [cornellcollege.edu]

Clear record of mass mortality, like you expect, requires exceptional preservation such as that captured in the Burgess Shale. That isn't the case for the Diadema, or for the Hell Creek formation.

And yes, of course you can associate things at 13cm. The number of vast changes in flora and fauna at the K/T boundary match up as well as could be expected with the Iridium spike and other impact markers. This is strong evidence that there is an association.

Re:Wait a fricken' second. (1)

DrSlinky (710703) | more than 3 years ago | (#36757666)

Mod this guy up, please

Re:Wait a fricken' second. (1)

pnewhook (788591) | more than 3 years ago | (#36754924)

Yes, because the earth builds up universally evenly mm by mm.

Re:Wait a fricken' second. (0)

Anonymous Coward | more than 3 years ago | (#36756102)

Might I suggest you actually crack open a science book?

huh? (4, Interesting)

vlm (69642) | more than 3 years ago | (#36754154)

We collected rock samples above and below the horn to determine the exact placement of the K/T boundary, and were surprised to see that the horn was no more than 13 cm below it.

A new fossil discovery has suggested that dinosaurs were alive right up until the asteroid impact

Speaking as a guy living in a county where the only non-service blue collar jobs left are at the local rock quarry, and having a geologist as a roommate two decades ago, I speak with profound scientific authority that those two quotes only go together if you define "right up until" as being about one zillion years. I suspect most readers define "right up until" on a somewhat shorter scale, like the time difference between the local news and american-idle, not zillions of years. (waves rolled up newspaper) Naughty journalist! Naughty!

"right up until" 13 cm of rock.

I am completely unaware of any political or cultural reason for the authors to be blind to this problem. I have no dog in the fight that I'm aware of. Just saying 13 cm of rock is not "right up until"

It MIGHT be that the real story is on a "bones per cm" basis this raises the curve implying the rate does not "tail off" (get it? dinosaur tail?) until the boundary, but that's not how the journalists are reporting it, as if the tip of the fossil was touching the boundary or chemical analysis of the fossil shows the dinosaur died during the boundary event.

Re:huh? (2)

Paltin (983254) | more than 3 years ago | (#36754734)

In geologist terms, 13cm is "right up until". Add in the Signor-Lipps effect and it's statistically indistinguishable.

http://en.wikipedia.org/wiki/Signor%E2%80%93Lipps_effect

Re:huh? (2)

sensei moreh (868829) | more than 3 years ago | (#36754766)

Two points to consider:
  1. The K-T boundary position is very well-constrained; the uncertainty regarding its exact age is irrelevant..
  2. Sedimentation rates are estimated to have ranged from 52 to 81 meters per million years. Thus 13 cm represents no more than 2500 years.

Now, is it possible, based on the available evidence, that the last dinosaur died out 2500 years before the big meteorite impact at the Cretaceous-Tertiary boundary? Certainly. However, is it likely? As a geologist, I'd have say NO!

Re:huh? (2)

Paltin (983254) | more than 3 years ago | (#36755058)

>Sedimentation rates are estimated to have ranged from 52 to 81 meters per million years. Thus 13 cm represents no more than 2500 years.

Sedimentation rates are not constant. They tend to come in fits and bursts. I would not draw that conclusion from the evidence.

Re:huh? (1)

Will.Woodhull (1038600) | more than 3 years ago | (#36755830)

While I realize that as a geologist you may not have much more understanding of the climate and weather considerations involved than I do, but since I know basically nothing about climate, weather, or geology, you might have a better idea of what was going on during the K-T events than I do.

So this big old rock slams into the Earth and makes enough dust out of itself to create the world-wide iridium enriched sedimentary deposits that are the K-T boundary. And in so doing, creates a very long winter.

So how long does it take for all that dust to actually settle? How much other sediments brought about by the more rapid erosion of the early part of the Long Winter would bury the remains of the megafauna before most of the asteroid dust was deposited?

It would seem that some gap between the last dinosaur fossils and the iridium layer should be expected, but would this be only millimeters, or is 300 centimerters actually a reaonable expectation?

extinctions (4, Interesting)

jollyreaper (513215) | more than 3 years ago | (#36754184)

The thing that I always wondered about with the asteroid impact theory is that we have several species of large reptiles that survived the extinction event. While I'm no scientist, I'm wondering if there might not have been some form of communicable disease that was stressing the dinosaur population beforehand that accounts for the gradual diminishing of fossils in the record and the asteroid impact might have been a coup de grace. I find it hard to imagine that sea turtles and crocadillians would survive while various marine reptiles did not -- moasaurs, plesiosaurs, icthyosaurs, etc. I suppose there will be no easy answers.

Re:extinctions (2)

Paltin (983254) | more than 3 years ago | (#36754762)

This is one of the bigger problems with the impact hypothesis. Also, amphibians were largely unaffected, and they tend to be very sensitive to environmental problems. Impact having an important contribution to the extinction is still the leading hypothesis, even if there are some things that aren't understood.

Re:extinctions (-1)

Anonymous Coward | more than 3 years ago | (#36754862)

From your post, I believe you when you say, "I'm no scientist..."

Re:extinctions (2)

ArsonSmith (13997) | more than 3 years ago | (#36755598)

how dare you deny the impact theory. Just because there's valid questions to it doesn't mean it's not true and we should blindly believe everything that is said about it. Raise taxes and fund steps that may or may not do any good.

Re:extinctions (1)

Michael Woodhams (112247) | more than 3 years ago | (#36756392)

"...some form of communicable disease that was stressing the dinosaur population..."

Try rewriting that as "...some form of communicable disease that was stressing the mammal population..." - it doesn't really make sense, does it? Dinosaur diversity back then was similar to mammal diversity now* - one disease isn't going to account for all, or even a large fraction, of them.

However, the dinosaurs may well have been stressed by evolving mammal and bird competitors - some think that this was the primary reason for their extinction, with the asteroid impact being secondary or even uninvolved.

* Disclaimer: I'm not an expert on dinosaur or mammal diversity.

Re:extinctions (1)

the biologist (1659443) | more than 3 years ago | (#36757876)

Given that dinosaurs rose to prominence after mammals were already scurrying around... I don't think the stress of the mammals is relevant.

Jumping to conclusions (2)

Translation Error (1176675) | more than 3 years ago | (#36754256)

It sounds like some people are really jumping to conclusions here. While finding a fossil from the time of the asteroid impact does indicate all dinosaurs hadn't died out before then, it doesn't mean they weren't gradually dying out due to environmental changes.

Someone dying when a rock fell on his head isn't proof he wasn't wasting away from a terminal disease.

Re:Jumping to conclusions (1)

MaxBooger (1877454) | more than 3 years ago | (#36754614)

They must have got the mat.

Re:Jumping to conclusions (1)

Paltin (983254) | more than 3 years ago | (#36755098)

Gradual extinction is still a possibility, but that's been covered by other studies and there is little to no evidence that specifically supports it.

What this paper does way in on is the claims that the extinction happened a long time (3m of rock worth of time) before the impact. If this is an unreworked bone, those claims are dead.

Re:Jumping to conclusions (1)

ArsonSmith (13997) | more than 3 years ago | (#36755652)

Just like a loose correlation between atmospheric carbon and temperature rise doesn't mean SUVs are killing the earth.

Not dead yet! (1)

tverbeek (457094) | more than 3 years ago | (#36754270)

I have a living alligator here that would like to argue with that "last dinosaur" designation.

Re:Not dead yet! (3, Funny)

Urkki (668283) | more than 3 years ago | (#36755106)

Alligators are not dinosaurs, they're Crurotarsi [wikipedia.org] , which are well known to deeply hate dinosaurs for playing dirty tricks on 'em back in the Triassic-Jurassic transition. So for your own sake, don't even mention dinosaurs to your pet alligator, and especially don't start an argument about it! Only thing the alligator is going to like about the argument is taste of your ripped-off limbs!

Re:Not dead yet! (1)

jaroslav (467876) | more than 3 years ago | (#36755230)

That's true. You could have at least chosen a bird instead.

Re:Not dead yet! (0)

Anonymous Coward | more than 3 years ago | (#36755312)

I have a living alligator here that would like to argue with that "last dinosaur" designation.

Alligators are not dinosaurs, they're Crurotarsi

That's true. You could have at least chosen a bird instead.

I had a dead turkey on my lunch plate that would have liked to argue with that "last dinosaur" designation, but I ate it.

Re:Not dead yet! (0)

Anonymous Coward | more than 3 years ago | (#36757778)

alligators are not dinosaurs. Birds are.

Re:Not dead yet! (1)

Em Adespoton (792954) | more than 3 years ago | (#36755542)

Dinosaurs != reptiles.
However, I've seen a lot of birds hereabouts who would like to submit that they're pretty darn closely related to dinosaurs.

Maybe non-resistant species died off due to the dinosaur equivalent of an avian flu, and the rest adapted/mutated? The impact event likely hastened this process by completely eliminating species who couldn't adapt quickly enough... leaving us with quickly adapting species that continued to adapt to compete with the uprising of mammalian and insectoid species.

I always wonder at the fact that flying relatives survived, but marine relatives didn't -- and reptiles did.

Re:Not dead yet! (1)

Randle_Revar (229304) | more than 3 years ago | (#36757674)

You could make a better case for a dinosaur being an alligator than vice versa. Your post would work a lot better if you cited your pet parakeet.

Fossils of the mass extinction (1)

Fractal Dice (696349) | more than 3 years ago | (#36754576)

One would think that the upheavals of the extinction event would have created some mass graveyards that could be found at the layer itself. I realize that in the grand scheme of things, the one wiped out generation is a statistical blip relative to the millions of generations that came and went through the normal lives and deaths, but given the scale of the disruption to normal ecology, it would be nice to find boneyards right on the KT boundary event itself.

Re:Fossils of the mass extinction (1)

the biologist (1659443) | more than 3 years ago | (#36757902)

If every deer in the USA dropped dead right now, would you expect to find mass graveyards? Mass fossil graveyards are very unusual things. There is no expectation of ever finding a boneyard coinciding with the KT boundary event.

Poor theories (0)

Anonymous Coward | more than 3 years ago | (#36755538)

Dinosaurs could not have died from climate change. They didn't have SUVs.

Stupid heads.

Questionable evidence (1)

Qatz (1209584) | more than 3 years ago | (#36755694)

I always take such finds with a grain of salt. Especially when there are a number of theories that are competing with it. First off there is a large margin of error in the K-T boundary. Second it was an asteroid may have *GASP* moved a lot of dirt, and possibly brought things closer to the surface.

La la la morons (1)

ronmon (95471) | more than 3 years ago | (#36758318)

Like any catastrophic event, a chain of events leads up to a final point of failure. The straw that broke the camel's back, as it were (at most). Almost never does one factor result in the collapse of an entire system.
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