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Posted

Thanks too Arc for your broad allowance for my digressions here. Happy New Year again all. :)

 

I'm getting a lot out of this myself. I'm planing on doing a series of images next fall, either one a day or maybe every other day of the subject area. I would like to take them from about 3 to 5 meters up. A fixed camera with remote shutter would be ideal. Make a nice slideshow of the development of the hoard piles. The area is lighted at night so a night shot would be nice if the worms are big enough to get a head count and a shot of them foraging.

Posted

I'm getting a lot out of this myself. I'm planing on doing a series of images next fall, either one a day or maybe every other day of the subject area. I would like to take them from about 3 to 5 meters up. A fixed camera with remote shutter would be ideal. Make a nice slideshow of the development of the hoard piles. The area is lighted at night so a night shot would be nice if the worms are big enough to get a head count and a shot of them foraging.

Excellent. Beyond the cameras, I have learned a fair amount about worms that I didn't know; tant mieux. If nothing else this all seems in the spirit of science discussion as it should be.

 

Onward then. In your OP I was interested to learn that many earthworms in the US are not native and that these invasive species are doing -and have done- severe damage to forest ecosystems. Equally if not more interesting was finding that we here in the Pacific Northwest United States have some very large species of native earthworms.

Here's a local link from Washington State University that outlines this situation: >> Are Worms Natural? The Global Worming Debate

 

Beyond that in space and time is the -perhaps- little known last scientific book by Mr. Darwin. While I have known of it for many years I can't say that I ever read more than some citations from it. However, in researching the work for this post I found the full monty in PDF format and I have saved the file and will be reading it in its entirety. For any and all interested in joining me in the venture, here is the link: >> The Formation Of Vegetable Mould, Through the Action of Worms, with Observations on Their Habits by Charles Darwin, LL.D., F.R.S. With Illustrations 1881

:)

Posted (edited)

Excellent. Beyond the cameras, I have learned a fair amount about worms that I didn't know; tant mieux. If nothing else this all seems in the spirit of science discussion as it should be.

 

Onward then. In your OP I was interested to learn that many earthworms in the US are not native and that these invasive species are doing -and have done- severe damage to forest ecosystems. Equally if not more interesting was finding that we here in the Pacific Northwest United States have some very large species of native earthworms.

Here's a local link from Washington State University that outlines this situation: >> Are Worms Natural? The Global Worming Debate

 

Beyond that in space and time is the -perhaps- little known last scientific book by Mr. Darwin. While I have known of it for many years I can't say that I ever read more than some citations from it. However, in researching the work for this post I found the full monty in PDF format and I have saved the file and will be reading it in its entirety. For any and all interested in joining me in the venture, here is the link: >> The Formation Of Vegetable Mould, Through the Action of Worms, with Observations on Their Habits by Charles Darwin, LL.D., F.R.S. With Illustrations 1881

:)

 

Excellent indeed, this is the one I have been reading through the last couple of days;

 

http://darwin-online.org.uk/EditorialIntroductions/Chancellor_Earthworms.html

 

"Darwin’s young protégé George Romanes, to whom he had entrusted some unpublished parts of his ‘big book’ on species, reviewed Earthworms in the weekly science journalNature on 13 October. Romanes focused on Darwin’s astounding and totally original proofs of the intelligence of worms, while at the same time demonstrating that they were deaf and blind. Romanes cited, for example, Darwin’s experiments proving that worms selected which part of a leaf to pull down first into their burrows."

 

I think that is shown currently in the way they always have the needle points going outward. Very picky behavior.

Edited by arc
Posted

Excellent. Beyond the cameras, I have learned a fair amount about worms that I didn't know; tant mieux. If nothing else this all seems in the spirit of science discussion as it should be.

 

Onward then. In your OP I was interested to learn that many earthworms in the US are not native and that these invasive species are doing -and have done- severe damage to forest ecosystems. Equally if not more interesting was finding that we here in the Pacific Northwest United States have some very large species of native earthworms.

Here's a local link from Washington State University that outlines this situation: >> Are Worms Natural? The Global Worming Debate

 

Beyond that in space and time is the -perhaps- little known last scientific book by Mr. Darwin. While I have known of it for many years I can't say that I ever read more than some citations from it. However, in researching the work for this post I found the full monty in PDF format and I have saved the file and will be reading it in its entirety. For any and all interested in joining me in the venture, here is the link: >> The Formation Of Vegetable Mould, Through the Action of Worms, with Observations on Their Habits by Charles Darwin, LL.D., F.R.S. With Illustrations 1881

:)

Read that first article; very interesting. I've always had a soft spot for worms and humus. I am not averse to saving a worm stranded on a path to be placed back on a friendlier surface. I am in agreement with the author: it is not the "invasive" worms fault; it's us.

Posted (edited)

Excellent indeed, this is the one I have been reading through the last couple of days;

 

http://darwin-online.org.uk/EditorialIntroductions/Chancellor_Earthworms.html

Holding out on us!? :lol: That's the page that led me to the PDF that I linked to. Seems they have copies of different editions.

 

"Darwin’s young protégé George Romanes, to whom he had entrusted some unpublished parts of his ‘big book’ on species, reviewed Earthworms in the weekly science journalNature on 13 October. Romanes focused on Darwin’s astounding and totally original proofs of the intelligence of worms, while at the same time demonstrating that they were deaf and blind. Romanes cited, for example, Darwin’s experiments proving that worms selected which part of a leaf to pull down first into their burrows."

 

I think that is shown currently in the way they always have the needle points going outward. Very picky behavior.

I've just started but looking forward to Chuck's ascertainments of wormy intelligence.

Read that first article; very interesting. I've always had a soft spot for worms and humus. I am not averse to saving a worm stranded on a path to be placed back on a friendlier surface. I am in agreement with the author: it is not the "invasive" worms fault; it's us.

In The Botany of Desire, a story is told of Johnny Appleseed throwing away his shoe to punish his foot for having stepped on a worm. As to the path, Chuck makes some mention of them in his introduction in The Formation of Vegetable Mould.... and it seems that it may be misplaced to judge a worm on a path as being on an unfriendly surface. I would quote some germane bits but the PDF text copies as an image and I'm not predisposed at the moment to type it out. By all means have a look as I think you will enjoy. :) Edited by Acme
Posted

About those pine needles and why they are pulled into the burrow by there base, that link by Acme;

 

http://darwin-online.org.uk/converted/pdf/1881_Worms_F1357.pdf

 

Chapter II has many observations of the worms and their interactions with pine needles. Page 77 has this observation;

 

post-88603-0-95472900-1420344650_thumb.png

 

They (C. Darwin and his son Francis) had fixed the pointed ends together in various ways to decipher the selection processes that the worms used in handling the needles and the reasons behind the observed preference the worms had.

Posted (edited)

About those pine needles and why they are pulled into the burrow by there base, that link by Acme;

 

http://darwin-online.org.uk/converted/pdf/1881_Worms_F1357.pdf

 

Chapter II has many observations of the worms and their interactions with pine needles. Page 77 has this observation;

 

attachicon.gifdarwin online.org.uk converted pdf 1881_Worms_F1357.pdf pine needles.png

 

They (C. Darwin and his son Francis) had fixed the pointed ends together in various ways to decipher the selection processes that the worms used in handling the needles and the reasons behind the observed preference the worms had.

Nice find Arc! Alas my reading of Darwin has been stalled today due to the arrival of my new camera and the reading of its manual. (And I haven't taken a single photo yet. :o) I will get to it. Perhaps there's a dab of resin at the needle's base that plays a roll in the selection. Something to do with closing the hole, or getting a good lip grip, or perhaps with their diet. ???

Edited by Acme
Posted

Nice find Arc! Alas my reading of Darwin has been stalled today due to the arrival of my new camera and the reading of its manual. (And I haven't taken a single photo yet. :o) I will get to it. Perhaps there's a dab of resin at the needle's base that plays a roll in the selection. Something to do with closing the hole, or getting a good lip grip, or perhaps with their diet. ???

 

I think it is the shape of the knob and the grip it provides but wouldn't it be something if it was a subtle sweet sugar taste that the worm can detect in those crevasse of the knob where sap would have passed between the needle (leaf) and the branch.

 

post-88603-0-37054400-1420350414_thumb.png

Posted

It would seem that they pull pine needles by the base because that is the easiest way to pull them into their holes. They do this in a tactile manner and will reject it if it is not orientated the right way the first time they pick it up. The function of these objects is to block the holes up in colder weather to stop them drying out due to air-circulation and reduced humidity. They will also strongly tend to pull broad-based leaves by the pointed end. Darwin isolated this tendency using paper triangles for them to go at and the pointed ends tended to get pulled in first.

 

http://www.psychology.gatech.edu/psyc3031/Behaviorism%20Behavior%20and%20Philosophy/1982%20-%20Vol%2010%20No%202/05%20Darwin%27s%20Earthworms%20A%20Case%20Study%20in%20Evolutionary%20Psychology.PDF

Posted

If they like sugar, use it to catch them to aquarium or jar.

Let them follow line of sugar, to place where they won't be able to get out.

Dig hole in the ground and place jar/aquarium there, so it will be perfectly lined up with the ground.

+ camera recording :)

 

Then earthworms put to aquarium with soil.

Place few randomly aligned needles on top.

And then observe what they do (or not) to needles.

Posted (edited)

It would seem that they pull pine needles by the base because that is the easiest way to pull them into their holes. They do this in a tactile manner and will reject it if it is not orientated the right way the first time they pick it up. The function of these objects is to block the holes up in colder weather to stop them drying out due to air-circulation and reduced humidity. They will also strongly tend to pull broad-based leaves by the pointed end. Darwin isolated this tendency using paper triangles for them to go at and the pointed ends tended to get pulled in first.

 

http://www.psychology.gatech.edu/psyc3031/Behaviorism%20Behavior%20and%20Philosophy/1982%20-%20Vol%2010%20No%202/05%20Darwin%27s%20Earthworms%20A%20Case%20Study%20in%20Evolutionary%20Psychology.PDF

 

Well, Darwin thought there may be something on the knob.

post-88603-0-26353400-1420356430_thumb.png

 

 

post-88603-0-86252400-1420354831_thumb.jpg

Yet, it has that certain "STAY AWAY OR I'LL POKE YOUR EYES OUT" thing going for it.

Kind of a "The more needles you has sticking out of your burrow the better chance you have to live and breed" Did this just evolve as a deterrence.

 

If they like sugar, use it to catch them to aquarium or jar.

Let them follow line of sugar, to place where they won't be able to get out.

Dig hole in the ground and place jar/aquarium there, so it will be perfectly lined up with the ground.

+ camera recording :)

 

Then earthworms put to aquarium with soil.

Place few randomly aligned needles on top.

And then observe what they do (or not) to needles.

 

But then they will just get fat and stay inside playing video games. ^_^

Edited by arc
Posted

It would seem that they pull pine needles by the base because that is the easiest way to pull them into their holes. They do this in a tactile manner and will reject it if it is not orientated the right way the first time they pick it up. The function of these objects is to block the holes up in colder weather to stop them drying out due to air-circulation and reduced humidity. They will also strongly tend to pull broad-based leaves by the pointed end. Darwin isolated this tendency using paper triangles for them to go at and the pointed ends tended to get pulled in first.

 

http://www.psychology.gatech.edu/psyc3031/Behaviorism%20Behavior%20and%20Philosophy/1982%20-%20Vol%2010%20No%202/05%20Darwin's%20Earthworms%20A%20Case%20Study%20in%20Evolutionary%20Psychology.PDF

yes. That reminds me this belgian joke, second here.

 

Two Belgians go to Laponia hunting reindeer (caribou).

They rent guns, a snow caterpillar track jeep and hire an eskimo guide for a week.

After two days of search in the frozen woods, they find a group of caribous. They step out the jeep, and silently they approach the animals. With some help from the eskimo guide, they finally manage to shoot a beautiful caribou. So they walk in the snow, get next to the dead caribou. They tie a rope to his rear legs, and pull it in direction of the jeep.

The eskimo guide explains that because of the direction of the caribou's fur, it would be easier to tie the rope at the antlers so that the deer can slide smoothly on the snow.

And so they do.

_Well, our eskimo guide was right, it is much easier now, says the first Belgian.

_Yes, but we are getting more and more away from the jeep, replies the other.

 

Posted (edited)

 

attachicon.gifphoto (8).JPG

Yet, it has that certain "STAY AWAY OR I'LL POKE YOUR EYES OUT" thing going for it.

Kind of a "The more needles you has sticking out of your burrow the better chance you have to live and breed" Did this just evolve as a deterrence.

 

I think those needles may have a purpose other than or in addition to a deterrent strategy.

 

post-88603-0-47894800-1420383424_thumb.pngpost-88603-0-89546700-1420384843_thumb.jpg

 

As noted the worms spend a considerable amount of time at their burrow's opening. Those needle would give the worm a slight advantage in the sense it would cause the bird to be more cautious in the last few cm of its approach. But more important they would behave as the whiskers on a mouse and forewarn the worm of the approaching bird. Striking the needles first would undoubtedly increase the worms perception of the imminent danger and give it that fraction of a second advantage it would not have without those needles sticking up above its opening. They are both a deterrent and an early warning device.

 

 

I think it is the shape of the knob and the grip it provides but wouldn't it be something if it was a subtle sweet sugar taste that the worm can detect in those crevasse of the knob where sap would have passed between the needle (leaf) and the branch.

 

post-88603-0-41225600-1420388065_thumb.png post-88603-0-94327300-1420388597.jpg

post-88603-0-34665200-1420388639.jpg

 

http://www.deanza.edu/faculty/mccauley/6a-labs-plants-04.htm

 

"Phloem transports the sugars that are produced in photosynthesis from the leaves to the rest of the plant. The phloem cells are small and thin-walled; in this slide, as in many others, the phloem cells appear blue."

 

Given the choice I can't see why the worm wouldn't take the opportunity to sample the sweetness of the needle by tasting the sugars

at the base or fascicle end of the needle. It may be an opportunity to reject a bad needle and not waste the energy to transport it.

 

edit spelling.

Edited by arc
Posted (edited)

You can download The Formation of Vegetable Mould by Charles Darwin Gutenberg Press have scanned it and released it for the public in various formats or online viewing. If you want it like .PDF format then EPUB is like that. I use SumatraPDF which will open it as well as PDF and other formats.

Edited by StringJunky
Posted (edited)

You can download The Formation of Vegetable Mould by Charles Darwin Gutenberg Press have scanned it and released it for the public in various formats or online viewing. If you want it like .PDF format then EPUB is like that. I use SumatraPDF which will open it as well as PDF and other formats.

 

Thanks String. That old type does have a certain quaintness to it though. ;)

Edited by arc
Posted

You can download The Formation of Vegetable Mould by Charles Darwin Gutenberg Press have scanned it and released it for the public in various formats or online viewing. If you want it like .PDF format then EPUB is like that. I use SumatraPDF which will open it as well as PDF and other formats.

Indeed. I referred to the downloadable PDFs at the Darwin Society link I gave in post #27. The text images that Arc has been posting come from similar, if not the same scans.

...Given the choice I can't see why the worm wouldn't take the opportunity to sample the sweetness of the needle by tasting the sugars

at the base or fascicle end of the needle. It may be an opportunity to reject a bad needle and not waist the energy to transport it.

However, on pages 58-59 Darwin says:

...In a gravel walk in my garden I found many hundred leaves of a pine-tree (P. austriaca or nigricans) drawn by their bases into burrows. The surfaces by which these leaves are articulated to the branches are shaped in as peculiar a manner as is the joint between the leg-bones of a quadruped; and if these surfaces had been in the least bit gnawed, the fact would have been immediately visible, but there was no trace of gnawing. Of ordinary dicotyledonous leaves, all those which are dragged into burrows are not gnawed. ...

I still think you may learn something by coloring the needle tips, though food coloring may be a better choice than the 'paint' I first suggested. Using different colors for loose needles and needles already pulled into burrows you can get some notion of their movement. You would be able to see if needles disappear down the burrows or stay more or less in place at the top, and you can pull out some needles that have been in place a while to see if the ends have been gnawed.

 

Now that we have thawed you may see the activity resumed. :)

Posted

Indeed. I referred to the downloadable PDFs at the Darwin Society link I gave in post #27. The text images that Arc has been posting come from similar, if not the same scans.

Do you know, I thought you mentioned it but couldn't see it at the time. This one is a cleaned up version with no marks on the pages ...probably used OCR.

Posted (edited)

 

I think those needles may have a purpose other than or in addition to a deterrent strategy.

 

attachicon.gifdarwin online.org.uk converted pdf 1881_Worms_F1357.pdf 3.pngattachicon.gifphoto (8).JPG

 

As noted the worms spend a considerable amount of time at their burrow's opening. Those needle would give the worm a slight advantage in the sense it would cause the bird to be more cautious in the last few cm of its approach. But more important they would behave as the whiskers on a mouse and forewarn the worm of the approaching bird. Striking the needles first would undoubtedly increase the worms perception of the imminent danger and give it that fraction of a second advantage it would not have without those needles sticking up above its opening. They are both a deterrent and an early warning device.

 

When a worm enters it burrow does it go head first or tail end first and turn around You would think it might be carrying the needle in its mouth end, which seems to imply it reverses into its burrow. Would it block its own escape route?

Or is it just poking these needles into the worm caste and letting the caste hold onto the base as it solidifies. If that is the case the worm is actually building a protection for itself.

Edited by Robittybob1
Posted

When a worm enters it burrow does it go head first or tail end first and turn around You would think it might be carrying the needle in its mouth end, which seems to imply it reverses into its burrow. Would it block its own escape route?

 

he characteristic wriggling of earthworms is accomplished by the contraction of two kinds of muscles. When the short muscles that circle each segment (like lots of rings on a finger) contract, the worm gets thinner and longer. When the long muscles that connect all the segments contract, the head and tail are pulled toward each other, and the worm becomes short and fat. Depending on which end of the worm is anchored, the worm can move along the surface of the ground or through its burrow effectively in either direction, head first or tail first.

 

http://lhsfoss.org/fossweb/teachers/materials/plantanimal/earthworms.html

Posted (edited)

 

When a worm enters it burrow does it go head first or tail end first and turn around You would think it might be carrying the needle in its mouth end, which seems to imply it reverses into its burrow. Would it block its own escape route?

 

he characteristic wriggling of earthworms is accomplished by the contraction of two kinds of muscles. When the short muscles that circle each segment (like lots of rings on a finger) contract, the worm gets thinner and longer. When the long muscles that connect all the segments contract, the head and tail are pulled toward each other, and the worm becomes short and fat. Depending on which end of the worm is anchored, the worm can move along the surface of the ground or through its burrow effectively in either direction, head first or tail first.

 

http://lhsfoss.org/fossweb/teachers/materials/plantanimal/earthworms.html

 

When a worm produces castes near its burrow you would assume that material exits the tail end. So the worm is head down tail up at that stage. So maybe they manipulate the needles with their tail end rather than their head end.

When a worm is in a hurry does it go head first or tail first? OK once in their burrow they can move forward or backward but that is not quite the same as what I was wanting to know.

Edited by Robittybob1
Posted

When a worm enters it burrow does it go head first or tail end first and turn around You would think it might be carrying the needle in its mouth end, which seems to imply it reverses into its burrow. Would it block its own escape route?

Or is it just poking these needles into the worm caste and letting the caste hold onto the base as it solidifies. If that is the case the worm is actually building a protection for itself.

They -for the most part- anchor themselves in the burrow by their posterior end and stretch out the anterior [mouth] end as they search about for food and plugs. Darwin says that in the absence of leaves or twigs they will plug/cover their burrows with stones. He noted one instance that he observed of a stone 2oz in weight being pulled to cover the burrow and that the gripping action of the mouth is largely one of suction.

 

I suggest you read Darwin along with Arc and I -if not StringJunky too- as it covers a great deal that we might otherwise speculate on.

Posted

I suggest you read Darwin along with Arc and I -if not StringJunky too- as it covers a great deal that we might otherwise speculate on.

I shall most definitely read it. I want to be an oligochaetologist when I grow up.

Posted

as it covers a great deal that we might otherwise speculate on.

 

But that's the best part! :unsure:

Posted

 

...as it covers a great deal that we might otherwise speculate on.

But that's the best part! :unsure:

 

:lol: While I do [obviously] enjoy the investigation and speculations involved, the better part -in my view- is in the knowing. After all, it is knowledge that is power and not speculation. :)
Posted

:lol: While I do [obviously] enjoy the investigation and speculations involved, the better part -in my view- is in the knowing. After all, it is knowledge that is power and not speculation. :)

I don't believe what was said e.g. "a worm moving a two ounce stone". I'll believe that when I see it.

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