Fossil of ancient spider attack only one of its type ever discovered

Oct 08, 2012
This is the only fossil ever discovered that shows a spider attacking prey in its web. Preserved in amber, it's about 100 million years old. Credit: Oregon State University

(Phys.org)—Researchers have found what they say is the only fossil ever discovered of a spider attack on prey caught in its web – a 100 million-year-old snapshot of an engagement frozen in time.

The extraordinarily rare fossils are in a piece of amber that preserved this event in remarkable detail, an action that took place in the Hukawng Valley of Myanmar in the Early Cretaceous between 97-110 million years ago, almost certainly with dinosaurs wandering nearby.

Aside from showing the first and only of a spider attacking prey in its web, the piece of amber also contains the body of a male spider in the same web. This provides the oldest evidence of in spiders, which still exists in some species but is fairly rare. Most spiders have solitary, often cannibalistic lives, and males will not hesitate to attack immature species in the same web.

"This juvenile spider was going to make a meal out of a tiny , but never quite got to it," said George Poinar, Jr., a professor emeritus of at Oregon State University and world expert on insects trapped in amber. He outlined the findings in a new publication in the journal Historical Biology.

"This was a male wasp that suddenly found itself trapped in a ," Poinar said. "This was the wasp's worst nightmare, and it never ended. The wasp was watching the spider just as it was about to be attacked, when flowed over and captured both of them."

Spiders are ancient invertebrates that researchers believe date back some 200 million years, but the oldest fossil evidence ever found of a spider web is only about 130 million years old. An actual attack such as this between a spider and its prey caught in the web has never before been documented as a fossil, the researchers said.

The tree resin that forms amber is renowned for its ability to flow over insects, small plants and other life forms, preserving them in near perfection before it later turns into a semi-precious stone. It often gives scientists a look into the biology of the distant past. This spider, which may have been waiting patiently for hours to capture some prey, was smothered in resin just a split second before its attack.

This type of wasp, Poinar said, belongs to a group that is known today to parasitize spider and insect eggs. In that context, the attack by the spider, an orb-weaver, might be considered payback.

Both the spider and the wasp belong to extinct genera and are described in the paper. At least 15 unbroken strands of silk run through the amber piece, and on some of these the wasp was ensnared.

Its large and probably terrified eyes now stare for eternity at its attacker, moving in for the kill.

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Doyoulikeduckmeat
4.2 / 5 (5) Oct 08, 2012
I would love to know the size of the spider and wasp. I know in the south east of the US, we have golden orb spiders that are HUGE. They are often mistakenly called Banana Spiders by many locals. However my point is they live often with several males and Juveniles on the same web as the much larger female. The tensile strength of the Golden orb is way higher than steel. And the navy uses a chemical in their webs to make an under water adhesive for repairs on ships in emergency situations. Spiders are really quite fascinating animals that are very often over looked and hated. I try to teach kids who find them in the house to take them outside rather than kill, after all they eat much peskier bugs than themselves. 1 acre of land in the US holds around 2million spiders. Imagine the number of bugs needed to feed these buggers. Really quite amazing find, though I wish the article had more details than stated. Like the size of the spider and wasp and had shown the other spiders in the web.
packrat
3.5 / 5 (4) Oct 08, 2012
I know it's odd but what kind of trees have a lot of sap running out of them? From the amount of amber found over the years there must have been some type of tree that leaked all over the place.
dschlink
3 / 5 (1) Oct 08, 2012
Amber is a resin, not a sap. I've seen similar resins on pine trees that had been damaged.
eljo
5 / 5 (1) Oct 08, 2012
Sssst, the trees are watching...
Doyoulikeduckmeat
5 / 5 (1) Oct 08, 2012
Packrat, I think any conifer is noted for making the Amber or resin. They are damaged in some way and it leaks out to repair it. Lob-lolly pines in the south can secrete so much over night it will really amaze you. I would assume the trees of this period were lager, I do not know much about this period this spider came from. I do know conifers can produce buckets of this stuff very rapidly. Who ever is looking in our conifer forests in a few million years will be asking the same questions. Pine trees leak this stuff and if you get it on your hands, short of acetone you can just about forget getting it off. Most of the things trapped in this stuff is small though. "google" 'Leaking pine trees' and go to images. I just did but posting the link didnt work. There are tons of photos from this search phrase to give you a good idea, it is really quite surprising the way they "leak" this stuff.
CharlesRKiss
1 / 5 (8) Oct 09, 2012
I'm concerned. For three reasons I think the claim is bogus: 1) it's not a proven attack 2) the probability this configuration between two bugs being random is real -and, incidentally, can be measured by comparing other samples of non-attacking "two bugs in amber" 3) the motion of amber, I imagine, would likely disturb the attack and not preserve the state of motion. As it is, the rear legs of the spider appear contorted.

When we see two bugs in amber, in such close proximity, like a fly mounted on a beetle, is it prudent to claim it's a cross-species mating ritual, or that one is "caught" eating the other?

Sure would like more information.
lifeiznuts
1 / 5 (4) Oct 09, 2012
And what is that on the far right? I read recently that feathers are being found in amber. Feathers from dinosaurs! There is a school of thought that maybe the dinos were covered with feathers, not necessarily scales. That thing in the pictures looks like one strand on a feather. I wonder.......
Anda
4.7 / 5 (3) Oct 09, 2012
" between 97-110 million years ago, almost certainly with dinosaurs wandering nearby."

Why "almost"?...

And @lifeiznuts, there is no "school of thought" about feathered dinosaurs, there's a lot of evidence mainly found in China.
TheBoss
5 / 5 (1) Oct 09, 2012
@CharlesRKiss Now to bring you up to speed. Spider senses wasp is on web goes in for kill. At that moment, sap from the tree comes and covers both of them. Now the spider not being able to turn around tried back up hence the legs being benched, or it could of been from the sap it's self. I see what your saying with that it could be a possibility of finding two insects in one piece of amber. Now I'm gonna go with what they're saying and the spider almost had one last meal. Hurrah for Science!!
Doyoulikeduckmeat
1 / 5 (1) Oct 09, 2012
This seems to be the same article about the same spider, but it clearly is not the same spider as the one pictured above. And there is no mention of the web. It seems the same in every other aspect except the 2 mentioned?

http://frenchtrib...s-period

CharlesRKiss
1 / 5 (2) Oct 09, 2012
@TheBoss

Seems for the "moment of the attack" to be frozen in amber would require an instantaneous coating of amber. My understanding of tree sap is that it moves slowly. To say that the moment of the attack is captured in amber is to say the moment of the breaking of the "twig" to the right has also captured, by the amber; or caused by the amber.
Doyoulikeduckmeat
1 / 5 (2) Oct 09, 2012
@ Theboss. Weren't those dino's proven to be fakes a few years back? At least I recall an article to this effect. Actually faking fossils was common not too long ago. I know you didnt claim they had feathers. I am no expert on the matter and obviously birds came from somewhere, but I think if dino's (or at least some of them) were covered in feathers then we would have reptiles today that had them, and or we would see more evidence that was not faked to this effect. Unless there is new "real" evidence I have not yet see.
packrat
3.4 / 5 (5) Oct 09, 2012
Packrat, I think any conifer is noted for making the Amber or resin. They are damaged in some way and it leaks out to repair it. Lob-lolly pines in the south can secrete so much over night it will really amaze you.


I live in the south and have seen them. I had one in my front yard till lightening got it that had been tapped for sap to make pitch for ships back in the late 1800's. All the pines in this area had been.(Wilmington NC had a big shipyard back then) Normally though the tree has to get a pretty good cut to start leaking a lot though. There must have been some animal back then that really like the taste of conifer bark from the amount of amber that's been found over the years.

@CharlesEKiss Pine tree sap will run very freely in the hot summer time for a few minutes after a spot get's damaged. It is fast enough to catch spiders and bugs. The one in my yard had caught a few ants on it's side where it had been damaged by my kids nailing bird feeder bottles to it
CharlesRKiss
3 / 5 (2) Oct 09, 2012
@packrat
Pine tree sap will run very freely in the hot summer time...

Yes, but won't the sap momentum also disrupt the positions and orientations of objects in it's path, ie. bugs.
packrat
3 / 5 (4) Oct 09, 2012
@packrat
Pine tree sap will run very freely in the hot summer time...

Yes, but won't the sap momentum also disrupt the positions and orientations of objects in it's path, ie. bugs.


Not necessarily if they are close to the damaged spot. Like I said in the other message, the tree in our yard managed to catch ants in the stuff. It will just dribble down the side and roll right over them and once it does, they are not going anywhere.
Doyoulikeduckmeat
3.3 / 5 (3) Oct 09, 2012
Pack is right. This stuff is like instant glue. As I said about, short of acetone its very hard to get this stuff off of you. Having experience with it, I could easily see something getting caught in it and being "frozen" in that spot/position to never move again. Its very viscous. The consistency is close to play-doo or chewing gum.

@pack. Over a few million years, I could imagine enough lightning strikes, wind storms, tornadoes,etc.etc. To cause the amount of amber. if you lop a branch off regardless of size its gonna "bleed" pretty good. Though I would guess some trees bleed more than others per injury. And again over a few million years of "bleeding" there may not have been an animal/insect that caused the damage, though I guess this is not totally out of the question either as a plausible cause. Think in terms of millions of years, and the amount of trees in just your area that gets lightning damage a year.
CharlesRKiss
1 / 5 (1) Oct 09, 2012
@Doyoulikeduckmeat

Its very viscous.

This is part of my point. The "slow" motion of the amber seems to contradict the speed at which "the moment of attack" must of taken place. Especially, when considering the surface across which (the bugs) the sap coated, ie. evenly and rapidly.

Surely, it's plausible that the amber had simultaneously adhered to many of the spiders appendages, say from "below", thus rendering it immobile and trapping it with this configuration.

In fact, it could have walked across the surface to consume an already trapped wasp, ultimately "sinking to the point of no return," as it munched.

But the impression I am getting from the researchers or the authors on this specimen, is that it is "just a split second before its attack," which contradicts the viscosity.

Now, maybe the spider is metaphorically still driving a car after a very long number of hours on the road, and the body doesn't mind falling asleep at the wheel, even if it means almost certain death.
lifeiznuts
1 / 5 (1) Oct 10, 2012
@ Theboss. I know you didnt claim they had feathers. I am no expert on the matter and obviously birds came from somewhere, but I think if dino's (or at least some of them) were covered in feathers then we would have reptiles today that had them, and or we would see more evidence that was not faked to this effect. Unless there is new "real" evidence I have not yet see.


This was very recent information. Dinosaurs it seems, evolved into birds. I read somewhere that chickens are actually evolved from T Rex! Anyway, there seems to be more evidence of feathers. More than were previously thought.
Doyoulikeduckmeat
3 / 5 (2) Oct 10, 2012
@ Charles. I guess it would depend on how exactly the spider and resin came into contact with each other. Say it fell on top of the spider while it was trying to eat. Or as you said the spider tried to walk across it (I dont think the surface tension is that high? maybe). I do know this stuff is like instant super glue. so perhaps your idea of what happened is correct. I suppose short of catching a few spiders and wasps and getting some sap, staging a few different ways for the insects to get trapped in it we may never actually know. Though I would not rule out the claim of the scientists. I guess there are so many variable it is plausible to happen this way. Though as also stated the ambient temperature would also factor in and effect the viscosity/surface tension of the resin. My nephews are out of school this week, red wasp and orb weaving spiders are common here in west TN, Conifer sap may be harder to find, but perhaps we may try a few of these to see what happens.
Doyoulikeduckmeat
1 / 5 (1) Oct 10, 2012
@ Life. Yes I heard the same thing about chickens. Last night I stumbled on some articles that some dino's such as Triceratops never even existed and were juveniles of a different dino all together. It very well could have I suppose. But it seems to me and in info I find on the feather thing, all the evidence is from China, where we know that a feathered dino fossil was faked in the past. Maybe they did, I think the field is way less advanced than we like to think and our knowledge on these animals is skewed by "superiority complexes" of some scientists. The next 20 to 50 years I hope will shed a lot more light on the subject, and may prove some of these dinos didnt exist at all as science is now publishing in Journals.

I will agree that more evidence is surfacing. And from what I have read feathers only fossilize under more rare circumstances than normal fossils. They are very rare from what I know (which isnt much). Time will tell this I think is a certainty.
lifeiznuts
1 / 5 (1) Oct 10, 2012
The next 20 to 50 years I hope will shed a lot more light on the subject, and may prove some of these dinos didnt exist at all as science is now publishing in Journals.

I will agree that more evidence is surfacing. And from what I have read feathers only fossilize under more rare circumstances than normal fossils. They are very rare from what I know (which isnt much). Time will tell this I think is a certainty.


I hope it's sooner rather than later! I won't be alive in 20-50 years! LOL! (But it really isn't funny. When I think of the things I will never find out about, I feel sick.)
Doyoulikeduckmeat
1 / 5 (1) Oct 10, 2012
That makes 2 of us life. I often wonder what I will miss out on. And it makes me hope there is an "afterlife" of one kind or another so that I can watch from where ever it is I will watch from. However I guess if there isnt I wouldnt know any better. I hate to dwell on it as you say it makes me sick. I would give most anything just for a glimpse at humans is 2000 more years, or 8000 more. I could only imagine where we might be. And I bet my wildest imagination doesnt even come close.
PhotonX
1 / 5 (1) Oct 13, 2012
The resin had only to trap the spider, no? The wasp was already trapped, and wasn't going anywhere regardless. A burst of wind at the wrong time, and there's the 'spider attack'. Though it might more aptly be named 'spider just sitting down to dinner'.
CharlesRKiss
not rated yet Oct 15, 2012
@PhotonX

I really like your explanation. It's plausible, with that dramatic element of the weather you see so many times in great tragedies throughout human history and literature!

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