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Did Insects Kill the Dinosaurs?
Ponca City, We Love You writes "Asteroid impacts, massive volcanic flows, and now biting, disease-carrying insects have been put forward as an important contributor to the demise of the dinosaurs. In the Late Cretaceous the world was covered with warm-temperate to tropical areas that swarmed with blood-sucking insects. A theory explored by researchers at Oregon State suggests these bugs carried leishmania, malaria, intestinal parasites, arboviruses and other pathogens. Repeated epidemics may have slowly-but-surely worn down dinosaur populations while ticks, mites, lice and biting flies tormented and weakened them. 'After many millions of years of evolution, mammals, birds and reptiles have evolved some resistance to these diseases,' says Researcher George Poinar. 'But back in the Cretaceous, these diseases were new and invasive, and vertebrates had little or no natural or acquired immunity to them.' The confluence of new insect-spread diseases, loss of traditional food sources, and competition for plants by insect pests could all have provided a lingering, debilitating condition that dinosaurs were ultimately unable to overcome."
Dinosaurs couldn't slap mosquitos, so they all caught malaria?
which is totally what she said
Ok, lets just make them all happy and say all of the above played a part. Giant meteor hits the Earth, causes dust to obscure the sun and weakens or kills a bunch of plant life. Meanwhile that same impact touches off a bunch of giant lava flows. Finally the dinosaurs already weakened by lack of food are subject to malaria and cough to death on dust clouds. There, all major doom scenarios all rolled into one. Please note, I'm not really serious with this... or am I?
Curiosity was framed, Ignorance killed the cat.
I learned it on MST3K during the movie Future War (which isn't set in the future and doesn't feature a war, natch.)
http://en.wikiquote.org/wiki/Mystery_Science_Theater_3000#Future_War
Thank you for not killing me.
Comment of the year
Dinosaurs? Bloodsucking Insects?
Is this another Music Industry article?
A French sci-fi author suggested that ants deliberately waged war on dinosaurs and killed them all (by invading their natural orifices and killing them from the inside) because their large size was detrimental to ant nests.
But frankly, I don't think new diseases would wipe out an entire order of life, all over the world, in all ecological niches, without wiping out other unrelated orders of life. In their hundreds of millions of years of existence, dinos had to fight off insects and diseases that were there before them, it couldn't just wipe them (and just them) off the face of the Earth in such a short time.
You can't take the sky from me...
parasites don't suddenly appear out of thin air and reduce their hosts to extinction
they gradually evolve in tandem with their hosts, and they make sure they always leach off the host's resources, and never kill their host
a parasite is not interested in killing its host. because then the parasite dies too
and a parasite is evolved to infect its host very carefully and specifically. dinosaurs did not suddenly get worms that no other creature ever got before. the worms evolved as the dinosaurs evolved
as for biting insects, this was a major new change. but again, it's not like mosquitoes materialized out of thin air and vampirically drained all the blood in the world. they slowly and gradually evolved to the job they do better and better, but never THAT good a job. never, never, did they kill their hosts. because this would then kill the mosquitoes
so frankly, this story is braindead on some fundamentals of evolution and parasites
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
this theory would fit nicely with the "world is only 6000 years old crowd"
i mean swarms of insects were mentioned in the bible (old testament, moses exodus part?) somewhere, i dont remember reading about asteroids in that book
The whole timeline appears a bit fubar here.
"After many millions of years of evolution, mammals, birds and reptiles have evolved some resistance to these diseases,' says Researcher George Poinar. 'But back in the Cretaceous, these diseases were new and invasive, and vertebrates had little or no natural or acquired immunity to them"
Um, the Cretaceous period lasted 75 million years. So while it's plausible that insects caused outbreaks of disease in localized populations I really don't see how anything of pandemic proportions can be inferred. As far as evolved resistance goes, well, the dinosaurs dominated the Earth for a LONG time. Much, much longer than mammals. Unless the diseases described all appeared about 65 million years ago, then there's just no logic here.
Besides that, dinosarus may have died out but many other species did not. This includes reptiles, which would have been affected by the pathogens according by these researchers.
The more I think about this, the more it smells like bullcrap.
I like basketball!!1!
You might ask what happened Mayan empire? http://en.wikipedia.org/wiki/Maya_collapse This insect thing might not be so far fetched as you think?
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...it was video, warming up for the radio star.
Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
Did insect-borne illnesses weaken the dinosaur species that went extinct before the meteor impact that ultimately led to their extinction, or did the geologic changes caused by the meteor impact weaken the dinosaurs to make them more susceptible to illness?
~Mike (Titan_X)
Admittedly I didn't RTFA, but are these scientists saying that the dinosaurs WEREN'T killed by the huge Chixulub asteroid? I thought it had been pretty much established that that was what happened (iridium concentrations at the K-T boundary, 65M-year old impact crater, 70% of other species kicking the bucket at the same time, etc.)
The sharks, ceolocanths, and 'gaters may beg to differ with ya...
Don't blame me, I voted for Kodos
It seems very unlikely that a whole planet of dinosaurs were killed by insects. It is actually very difficult for insects to cover an entire continent, let alone move from continent to continent. In current times, insects stowaway on ships and planes to travel large distances and between continents. Also, if this were true regarding reptiles, what about crocodiles? They've been living much longer than any of the dinosaurs and the lived in conditions where mosquitoes thrive. How do you explain them?
It might work! But only if that insects - along with carrying various diseases - also carried giant, planet-killing asteroids with them. If we just call the "Dinosaur Period" the Jurassic through Cretaceous, that lasted from 200 million years before now to 65 million years before now (+/- 5-10 million years). I find it kind of hard to swallow that Dinosaurs couldn't build up an immunity to disease over a period of 135 [i]million[/i] years. Viruses can evolve and change hundreds of times in the course of a human lifetime (which you can't even measure with Geologic time). If Viruses were around for 135 million years when Dinosaurs were around, the Dinosaurs had to have pretty hefty immune systems to be able to cope with all the new viruses evolving. And considering that they actually lasted until a giant rock fell out of the sky, I'd say that getting head colds probably didn't do them in.
Give a man a fire and he'll be warm for a day. But light a man on fire and he'll be warm for the rest of his life.
It's not specific blood-bourne pathogens, it's blood-bourne pathogens in general. We have lots of complicated mechanisms that have developed over millions of years of evolution that provide a lot of protection.
And yes, there are a number of genes that code for malaria resistance in human beings; they exist wherever malaria is common. The most well known (and most common?) is the sickle cell gene. But there are a number of other mechanisms that have evolved independently that protect people from malaria. If your ancestors had a lot of trouble with malaria, you are probably much more resistant to it than someone whose ancestors came from Norway.
OMG ZERG RUSH! :)
I take my children to see Madonna(..), but I never for once ever thought I was in the same business.Chris Rea.
Com'on. Somebody needs a graduate degree and/or funding gotta come up with some sort of original research, regardless of how far fetched it is. Welcome to the dark side of academia.
- Aids (originally from Chimps?) takes years to kill, allowing the host to infect others.
- Bubonic Plague was a disease for rats. It killed a lot but not to the extent of exterminating entire species. Humans have developed resistance.
- Ebola? Endemic in some monkey species, outbreaks amongst humans cause so much damage that the disease fails.
- Malaria: kills a lot, but humans have developed resistance here as well.
Now if you postulate Intelligent Design . . . Bye Bye Dinos.Mielipiteet omiani - Opinions personal, facts suspect.
There could be something to this theory. Flowering plants originates at about the same time dinosaurs conked out. And to aid pollination by insects, the plants started making high octane fuels (nectar, is almost pure sugar) and the co-evolution of insects and flowering plants raced ahead. There could be something to it, but still we would need more positive evidence. We still have to explain the iridium layer in sediments too.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Although "Dinosaur" is used very widely, and often used to refer to extinct reptiles like the Pliseosaur, Pteridon, or Leoplurodon; the groups wiped out were, properly speaking, the Therapods (popularly the T-Rex, Velociraptors, and their kin) and the Sauropods (Brachiasaur, Triceritops, etc). Neither of these groups survived the mass extinction at the end of the Cretatious period.
Sharks are sharks, Ceolocanths are fish, and Aligators are reptiles. Although all three forms date back very nearly how they look now to the time of the dinosaurs, it would be an equivocation to call them "dinosaurs" when discussing the "extinction of the dinoasurs".
Apologies for spelling, mine is pretty poor.
'But back in the Cretaceous, these diseases were new
They were new? I am by no means an authority on the subject, but from what I remember learning about evolution, one-celled-organisms came along before cell colonies. Further, small cell colonies (bugs and such) came around before big ones (dinosaurs and such). I even recall learning that the first self-replicating DNA strands were much more virus-like than bacteria-like...since the whole membrane and organelle system didn't come about until a bit later.
So, by the time the dinosaurs were around, the world should have already been densely populated with viruses, bacteria, and small bugs which could find the guts of a dinosaur to be fertile breeding grounds.
I really don't see how these things, and the diseases they cause, could have come around after the fact. Maybe some more sinister versions of them, more specifically targeted at the dinosaurs of the day, came around after the fact, but I don't think that alone would account for a mass extinction.
If you have corrections to offer, don't hold back (not that you would).
Between meteor strikes, volcanoes, ice ages, and mosquitoes, they didn't have a chance.
and all within the past 6000 years...
the first lawyer was probably the deathknell.
There is no intelligence involved in the parasite - they cannot make the decision not to wipe out the host species.
/frank
A Parasite that develops and is virulent enough to wipe out its host species will go extinct as a result of doing so. An evolutionary dead end, certainly, but undoubtedly an evolutionary dead-end that has occurred more than once in earthly history. Nothing and no one will step in to prevent this from happening (well, at least in my theology).
In that sense, a "successful" parasite is relatively weak, and establishes an equilibrium with one or more host species. As a species, it survives for eons. An "unsuccessful" parasite is strong, virulent, and species specific. As a species, it dies when it takes out the last host.
And the worms ate into his brain.
There's nothing about evolution which inherently prevents a species from ending itself...you just don't encounter self-eliminating species often because of survivor bias.
I'm waiting for the mosquito control bill to pass Congress. We need to get these lethal mosquitoes out of the hands of our young Dinolings. There can be no middle ground on this! The two week waiting period for mosquitoes is simply not enough!
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
I know of a similar theory to explain why mammals moved back to the sea... (Whales, dolphins, etc) The theory is that the whales were so pissed off at the mosquitos, that they went into the sea just to get a little relief. They stayed there too long, and so their arms and legs turned into fins and flippers. In case anybody is wondering who proposed the theory, well it was me. And no I don't have any scientific evidence to back it up. But it is certainly more plausible than the theory being discussed regarding the dinosaurs...
Brawndo: It's what plants crave!
"and the Sauropods (Brachiasaur, Triceritops, etc)"
Triceratops wasn't a sauropod. Like other marginocephalians, it was a member of one of three orithischian (bird hipped) groups (the other two are threophora which includes armoured dinosaurs such as ankylosaurus and stegosaurus, and ornithopods such as the hadrosaurs). Sauropods were saurischian (lizard hipped), and are therefore more closely related to therapods than either are to the ornithischians.
I'm not going to change your sheets again, Mr. Hastings.
In short, it is unlikely that biting insects could be responsible for all this chaos. The extinction was simultaneous, worldwide, and (in geological terms) instantaneous, it hit animals and plants, and it hit organisms on land and in the sea. Now, it turns out, probably not coincidentally, that at the same time all of this happens, a huge asteroid or comet impact- one of the biggest in the past half-billion years- takes place in the Yucatan, blasting dust into the stratosphere, sending tidal waves across Texas, and probably igniting much of North America in the process. An asteroid impact is probably capable of causing an extinction like this. Its doubtful that gnats, mites, and mosquitos could.
Dinosaurs were on their way out by the end of the Cretaceous
anyway. In N. America they had declined from about 35 genera
to about 12 genera by the end of this period. The #1 reason
for their decline was the dropping O2 levels in the atmosphere
caused by the intense volcanic activity that was occurring
due to the breakup of Pangea. O2 levels were about 35% at the peak
of the Cretaceous and are about 21% today. Dinosaurs got big because
they had lots of O2 to breathe. They also didn't need to be warm-blooded
because everywhere it was warm, anywhere from 5 to 10 degrees C. higher
on average than it is today. Big animals take a long time to heat up and
longer to cool off, so no need to be homeothermic.
The number two reason was probably cooling due to increased levels of
aerosols and particulites in the atmosphere from all the volcanism.
So it's getting harder to be a big animal when you can't breathe,
it's getting colder (and you can't regulate your body temp),
and your food supply is changing or disappearing.
Then along comes this pesky meteor that blasts a few billion cubic
meters of dust into the atmosphere and turns out the lights for a
year or two. No heat, no food, no O2, no survival if you need these in
quantity. That's one situation that our mammalian ancestors could cope with
though, because their survival demands were lower.
I've got your sig, right here.
Ummm...
Ow...that post hurt my head. Someone left the door unlocked and a paleontologist got in!!??
What is he thinking?
Doesn't he know that Slashdot is only for armchair experts, not actual ones?
"In other terms, birds are descendants and cousins of dinosaurs, but they are not a species of dinosaur."
Sorry, but that was an example of the common misconception I was trying to point out. Contrary to your proposal, birds _are_ a group of species of dinosaurs.
If all mammals, except the bats for example, went extinct, your favorite bat would not seize or stop being a mammal. And the number of very specific adaptations of the bats would NOT set them apart (sonar, leathery wings, wrinkled noses, large ears, etc). The bats would remain inside the mammal group, just as all the bird species remain inside the dinosaurs. Bats are specialized mammals and birds are specialized dinosaurs.
If a mosquito born disease would kill all mammals, the bats would die out too. Therefore it was probably not a disease that killed all dinosaurs and spared that group we now call birds.
.
You are correct. My post contained an unfortunate typo.
I'm not going to change your sheets again, Mr. Hastings.
The vast majority of flowers are intended to attract insects. Think about the most notorious disease-spreading insect: mosquitoes -- which are primarily nectar feeders (the males exclusively so). So it's not as if flowering plants only support the existence of cute fuzzy little insect species like butterflies and honeybees. Flowering plants form the base for a sizable percentage of the entire insect population, including many of the ones that spread diseases and parasites.
Insects aren't much better at eating cellulosic biomass than animals are, and blood alone isn't a particularly practical food-source. In fact, are there ANY insects that can subsist entirely on blood? Some arachnids do, but no insects. It's easy to see how the emergence of nectar-producing plants would give rise to vast array of new types of insects, some of which would then be willing to take a bite out of passing dinosaurs to supplement their diets.