[NatureNS] Wasp question

From: "Paul S. Boyer" <psboyer@eastlink.ca>
Date: Sat, 02 Oct 2010 20:49:23 -0300
To: naturens@chebucto.ns.ca
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Index of Subjects

More bemusing w

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We often hear this said about insects and how strong they are.

I suspect that the main reason insects seem so strong is merely the =
scale factor.  If ants are so mighty, why are there no really large ants =
around?  Clearly, there is a scale factor which limits their size.  It =
is not possible to build a viable ant larger than a certain size.

I cannot find any reference proving that ant muscles are actually =
stronger by weight than muscles in other creatures.  Who knows?  It =
might be interesting to find out.  But it seems to me that the relative =
strength of a muscle is roughly proportional to its cross-sectional =
area.  As one scales up the size of a muscle, the volume increases as =
the cube of the linear dimension, but the cross-sectional area only as =
the square.  So a bigger animal will have trouble keeping up =
proportionate strength as it gets larger.

We could see this in a jumping contest.  I have seen a wild Norway Rat =
leap laterally about 3 m, which is many times (perhaps x15) his length.  =
A human Olympic athlete can't jump proportionally so far; and a bear =
(strong as he seems to us) is even a shorter jumper.  And they say that =
an elephant is totally unable to jump at all!

Thus in a weight-lifting contest where the load is calculated as a =
multiple of the contestant=92s body weight, the small animals (other =
things being equal) should win.  Insects, of course, are not formed at =
all like vertebrates, and in their size range an exoskeleton could have =
many advantages.  Exoskeletons do not work at all in our size range, =
which is why there are not any really gigantic insects (except in our =
nightmares, or in sci-fi movies).

Similarly, we cannot scale humans down to ant size, and there are no =
mammals with that tiny an adult size.

Birds are another great example of scaling.  Most birds are small.  Only =
a few get very large, and as they do, they have more and more trouble =
taking off.  The largest cannot fly at all.

So, whenever we hear that a certain insect has remarkable abilities at =
lifting weight or jumping, we should be impressed =97 but not too much, =
for they are in a size range which puts them in a different league from =
us mammals.  Then if we can figure out the importance of the size factor =
in biomechanics, we will really be getting somewhere in understanding =
how different creatures work.


On 25 Sep 2010, at 4:25 PM, D W Bridgehouse wrote:

> Since wasps , bees and ants are lumped into same order of Hymenoptera =
its also interesting that ants can carry items 10 =96 50 times their own =
body weight.Ants are small but they are very strong for their size. If =
you were that strong you could lift an automobile. The ants carry or =
drag heavy loads for food back to their nests. The food may be parts of =
plants or bits of dead animals.
>=20
> More food for thought J
>=20
> =20
> =20
> From: naturens-owner@chebucto.ns.ca =
[mailto:naturens-owner@chebucto.ns.ca] On Behalf Of andy dean
> Sent: September-25-10 12:57 PM
> To: naturens@chebucto.ns.ca
> Subject: [NatureNS] Wasp question
> =20
>     Attention of any budding or professional entyologists in the =
group.
> =20
>  One morning recently my wife and I discovered about 50 dead wasps on =
the garage floor , just inside the door, and attributed it to a natural =
'end-of-season' phenomenon....does that seem correct?
>     More bemusing was the fact that whilst we sat with the garage door =
open, drinking our morning coffee, we twice witnessed a wasp fly in and =
after examining a corpse lift it and fly off with it.....anybody know =
what that was all about?
>     It was mind-boggling to realize that the weight of the corpse in =
relation to the live wasp would have been the equivalent of me lifting =
my wife bodily off the ground and flying off with her ......a sobering =
thought !
> =20
> Andy and Lelia Dean
> 86 Baden Powell Drive
> Kentville, N.S.
> (902) 678-6243


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<html><head><base href=3D"x-msg://40/"></head><body style=3D"word-wrap: =
break-word; -webkit-nbsp-mode: space; -webkit-line-break: =
after-white-space; ">We often hear this said about insects and how =
strong they are.<div><br></div><div>I suspect that the main reason =
insects <i>seem</i> so strong is merely the scale factor. &nbsp;If ants =
are so mighty, why are there no really large ants around? &nbsp;Clearly, =
there is a scale factor which limits their size. &nbsp;It is not =
possible to build a viable ant larger than a certain =
size.</div><div><br></div><div>I cannot find any reference proving that =
ant muscles are actually stronger by weight than muscles in other =
creatures. &nbsp;Who knows? &nbsp;It might be interesting to find out. =
&nbsp;But it seems to me that the relative strength of a muscle is =
roughly proportional to its cross-sectional area. &nbsp;As one scales up =
the size of a muscle, the volume increases as the cube of the linear =
dimension, but the cross-sectional area only as the square. &nbsp;So a =
bigger animal will have trouble keeping up proportionate strength as it =
gets larger.</div><div><br></div><div>We could see this in a jumping =
contest. &nbsp;I have seen a wild Norway Rat leap laterally about 3 m, =
which is many times (perhaps x15) his length. &nbsp;A human Olympic =
athlete can't jump proportionally so far; and a bear (strong as he seems =
to us) is even a shorter jumper. &nbsp;And they say that an elephant is =
totally unable to jump at all!</div><div><br></div><div>Thus in a =
weight-lifting contest where the load is calculated as a multiple of the =
contestant=92s body weight, the small animals (other things being equal) =
should win. &nbsp;Insects, of course, are not formed at all like =
vertebrates, and in their size range an exoskeleton could have many =
advantages. &nbsp;Exoskeletons do not work at all in our size range, =
which is why there are not any really gigantic insects (except in our =
nightmares, or in sci-fi movies).</div><div><br></div><div>Similarly, we =
cannot scale humans down to ant size, and there are no mammals with that =
tiny an adult size.</div><div><br></div><div>Birds are another great =
example of scaling. &nbsp;Most birds are small. &nbsp;Only a few get =
very large, and as they do, they have more and more trouble taking off. =
&nbsp;The largest cannot fly at all.</div><div><br></div><div>So, =
whenever we hear that a certain insect has remarkable abilities at =
lifting weight or jumping, we should be impressed =97 but not too much, =
for the