Eggs with legs experiment .

Talkenlate04

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So in the recent past some of you know I have seen B. Smithi eggs with legs latch onto their sibblings and suck them dry.

So I conducted two tests.

Test one I took out 10 fresh eggs with legs from my second sac and soaked the papertowl. Not enough to drown them but only soak the paper well.
2 hours later the slings have gained size in the abdomen from consuming water.

Test two was much more interesting. I prekilled green aphids and placed them close to the mouth parts of the newly hatched eggs. And this is what I whitnessed.

 

P. Novak

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That is awesome Ryan, great experiment! :clap:

They are actually eating them? That is amazing.
 

stk5m

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I had no idea eggs with legs had strong enough fangs to eat
 

Talkenlate04

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There have been a few others that have whitnessed eggs with legs eating sibblings. I just tested to see if it was an instinctual thing, maybe killing off their sibblings to get stronger and have a better chance once out of the sac. Or if they are just trying to feed. At this point I am not sure.
Still a long ways to go before I can have anything solid.
 

P. Novak

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There have been a few others that have whitnessed eggs with legs eating sibblings. I just tested to see if it was an instinctual thing, maybe killing off their sibblings to get stronger and have a better chance once out of the sac. Or if they are just trying to feed. At this point I am not sure.
Still a long ways to go before I can have anything solid.

Yes, but you are doing a great job proving this. Keep me updated!
 

moose35

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cool well keep up the work to see what happens. i'm curious to see. its very interesting. they sell some cheap usb mirroscopes that could take still with. they take very good pics. it would be a goodedition to the experiment.


moose
 

Talkenlate04

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Well thats the problem, other then seeing them eat, I dont know what else could be proved.
I am going to leave all those eggs with legs that eat an aphid seperate. Just to see if they molt faster or are bigger through the early instars.
Any other things anyone thinks I should be watching for?
 
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Bigboy

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Get a microscope and look for aphid "bits" in their gut contents.
 

Talkenlate04

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I actually have a microscope...... I just need to buy the camera attachment for it so I can photograph what I am seeing.To bad it costs almost a paycheck.
I have more sacs coming from other species, so it will be of use when I do get it someday.
 

moose35

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did you check ebay...the cam itself is like 50 bucks or so.
 

Taceas

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TalkenLate said:
Any other things anyone thinks I should be watching for?
Yeah, a font people can read. ;)

Interesting experiment. I would have expected their abdomens to have taken on a slightly green hue, though.
 

Talkenlate04

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Yeah, a font people can read. ;)

Interesting experiment. I would have expected their abdomens to have taken on a slightly green hue, though.
It is actually as the feeding goes longer. I just cant get my crap camera to stop flash glaring me.
I am actually more interested in the fact that they consumed water at such a young stage. The ones that have drank water are almost double the ones that have not. Ill try to get pics of that in the morning.


As for the font it looked big when I first did it. I am still new at computer photo stuff too. Ill try better next time.
 

Talkenlate04

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did you check ebay...the cam itself is like 50 bucks or so.
How will I know if it attaches to my scope?I really dont know beans about microscopes. This thing came from Intel computers and is meant to look at atoms. So needless to say its really fun to look at things. I even saw my own blood under a slide.
 

chrispy

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What kind of scope do you have? A disecting microscope is perfect and what Im looking for. Regular type scopes might magnify to far. Like for blood -at the cellular level. The Disecting scope I got to play with was amazing. The hairs on the legs or abdomen were like 1/4" apart in the screen. A small hair forest. It was so clear. The size ratio was like nothing Ive ever seen.

I thought the scope attachment was for your camera not the scope, all scope eyepieces should be the same size. It just has to fit your camera. Whoever made the camera should have an adapter for the camera if it works w/ scopes.
 

DrAce

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Meant to look at atoms?!

You have a scanning electron microscope at hand? I'm jealous! (sorry, that was a little sarcastic).

I think you've got a neat little experiment here. You've set it up well, and you have chosen some nice measurable features (growth rates, feeding or not, etc). Now I'm gonna stick my 'take-the-work-to-pieces' hat on... that way we can work out what would make this experiment better.

You're right... you will need to actually establish that the spiderlings are actually eating the aphids. They may just be attacking, and then the aphids are drying out. A weight gain would be an indication of this. Perhaps you can measure several of the feeding spiders together before, and after a feed (maybe with and without the aphid carcasses) to establish where the 'mass' is going. I appreciate that they don't weigh much, and there will be considerable uncertainty in this... but you mention that they grow considerably after a decent feed, so it might not be too bad.

Also, as neat as this experiment is, it doesn't actually establish feeding responses on siblings. A really hard-core researcher could argue that they can detect through some chemotaxic response that these were insects, and some feeding response was triggered (again, because they don't think very much). Many organisms with 'clutches' like this, scorpions, tadpoles, mantises etc are capable of detecting siblings. Why are the tarantulas not doing this?

I do think, however, that the feeding vs growth rates is a very important experiment, and you're doing what you need to, to make this a publishable experiment. If you want a hand with data analysis, etc, then give me, or some of the other 'science-buffs' out there a call... I'm thinking off my head of Cheshire, Thoth, Code-Monkey etc. If they have time, they would likely be able to pick it over with you. Also, some of them are entimologists, and have more experience with dealing with these types of systems...

Exciting experiments... keep us in the loop, please!
 

cacoseraph

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one tiny little suggestion for experiments.

while 10 subjects is certainly much better than one.... 20 or 50 would be even better

one of the problems with 10 subjects is that it can all too easily become 6 subjects, which is too little to really do any stats on

this is a large part of why i haven't taken on any more hardcore experiments... they are a massive pain in the ass =P



awesome awesome awesome subject matter, btw. this could have some really interesting implications for "delicate" spiderling species
 

Richard G

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This is a really fantastic experiment. It never even occured to me that S1 nymphs would be able to feed. It's given me the idea to try something similar with some of the S2 H.lividum nymphs I have at the moment. Fantastic!
 

Talkenlate04

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Here is a picture showing the noticable size difference between an egg with legs that had water and one that did not have water. This is a good picture and really shows they are consuming something at this stage.

 

kyrga

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Very cool experiment.

Just curious, what do you use to keep track of data? A computer program/database or old fashioned pen and paper?
 
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