lpetrich

In reference to MrDarwin's comment, a common creationist rhetorical technique is to point to excellent adaptations and then ask how they could be the result of evolution -- the implication being that they must have come into existence in one big jump.

Thus, they talk about camera eyes or bombardier-beetle sprays or honeybee hives, while leaving out lots of cases of less-developed eyes or different sprays or less-fancy hives like bumblebee hives and solitary-bee nests. Such examples make "one big jump" a very clearly superfluous hypothesis, since to go from a bumblebee-like ancestor to a honeybee is much less of a jump than from some "average" insect to a honeybee.

Another creationist argument may be phrased, "if honeybees are more advanced than bumblebees, then why do bumblebees continue to exist?" Honeybees do compete with other bee species, especially in places where honeybees have been introduced. However, bumblebees have some features that can given them an edge over honeybees in some circumstances. They have smaller hives, and they can survive harsher winters.

This last one is especially interesting. Honeybees survive winters by clumping in their hives and consuming the honey that they have built up over the previous summer; they cannot hibernate. This strategy has some limits; if the weather is too cold, then they cannot stay warm enough to collect honey, and they go hungry and freeze. However, bumblebees do not try to stay active during the wintertime; the queens hibernate and the others die.

This results in bumblebees being found farther north than honeybees.

[ September 23, 2002: Message edited by: lpetrich ]</p>

MrDarwin

I don't agree, because (AFAIK) this is true of all Hymenoptera, not just the groups with social members and their closest relatives. It may have played a part (in fact I'm sure it did) but doesn't answer my specific point, which is that eusociality arose independently in the Vespoidea and Apoidea, but that these two groups are each other's closest relatives, and these are the only groups of Hymenoptera in which eusociality evolved.

I suspect it's more likely a suite of characters:

• nest building
• hunting/gathering lifestyle (i.e., bringing food back to the nest, as opposed to parasitoids that lay eggs on prey and leave them)
• use of the ovipositor as a defensive weapon

I also found a few more interesting articles:

<a href="http://instruct1.cit.cornell.edu/courses/bionb424/students/dcg5/phylogeny.htm" target="_blank">Phylogeny of Apoidea</a> (note that this is not a cladogram, being a hypothesis of relationships constructed before cladistics was widely used in taxonomy; it's interesting to compare this tree to more recent morphological or molecular cladistic analyses). Eusociality occurs in 3 widely separated parts of the tree, in the families Halictidae, Anthophoridae, and Apidae. Parasocial species occur more widely, although in most cases the eusocial groups have parasocial relatives.

Compare that to <a href="http://entomologia.rediris.es/sea/bol/vol26/s3/articulo" target="_blank">this article</a> (in Spanish but you can still look at the trees) and this tree:



taken from <a href="http://bss.sfsu.edu/geog/bholzman/courses/Fall01%20projects/sbee.htm" target="_blank">here.</a> I'll let somebody else look into the lifestyles of the various bee families leading up to the social Apidae--but most are solitary, ground-nesting bees. And getting back to Ipetrich's original point, within the Apidae itself we can still find pretty much the full transition from parasocial to primitively social to eusocial.

[ September 23, 2002: Message edited by: MrDarwin ]</p>

Dr.GH

zygotecowboy, posting at ARN offered this article:

<a href="http://www.pnas.org/cgi/content/full/99/1/286" target="_blank">http://www.pnas.org/cgi/content/full/99/1/286</a>

PNAS: Evolution of sociality in a primitively eusocial lineage of bees.

Danforth BN.

Department of Entomology, Comstock Hall, Cornell University, Ithaca, NY 14853-0901, USA.

Eusociality is a major evolutionary innovation involving alterations in life history, morphology, and behavior. Advanced eusocial insects, such as ants, termites, and corbiculate bees, cannot provide insights into the earliest stages of eusocial evolution because eusociality in these taxa evolved long ago (in the Cretaceous) and close solitary relatives are no longer extant. In contrast, primitively eusocial insects, such as halictid bees, provide insights into the early stages of eusocial evolution because eusociality has arisen recently and repeatedly. By mapping social behavior onto well- corroborated phylogenies, I show that eusociality has arisen only three times within halictid bees (contrary to earlier estimates of six or more origins). Reversals from eusocial to solitary behavior have occurred as many as 12 times, indicating that social reversals are common in the earliest stages of eusocial evolution. Important attributes of social complexity (e.g., colony size, queen/worker dimorphism) show no obvious association with phylogeny, and some reversals to solitary nesting are related to host-plant switches (from polylecty to oligolecty). These results provide a glimpse of social evolution in its earliest stages and provide insights into the early evolution of advanced eusocial organisms.

[ September 23, 2002: Message edited by: Dr.GH ]</p>

Grumpy

And among a handful of <a href="http://www.junglephotos.com/animals/insects/treeweb.html" target="_blank">spider</a> species, I see. IIRC, <a href="http://eebweb.arizona.edu/Faculty/Aviles/Lab/bio_Leticia.htm" target="_blank">Letitia Aviles</a> of the University of Arizona was featured in a "Scientific American Frontiers" segment doing field studies of these critters.

Do IDers do this? With honeybees, I mean? I find it strange that this bee pamphlet would use such a hackneyed example and still claim to represent Intelligent Design. I thought the new "don't call us" creationists stuck to more esoteric subjects, like metabolic chains and cellular organelles.

We knew all along that it has never been more than a microscopic refinement of "That tree is pretty; God must have made it." It's just strange to see ID run out of examples (or cling to old ones) so quickly.

MrDarwin

Dammit, why didn't I find that article? That's exactly the kind of thing I was searching for on the web. (And Comstock Hall is where I took classes and later worked for several years!)

Non-praying Mantis

</strong>

When I made this comment, the point that I was attempting to make was that sex determination by ploidy status in the Hymenoptera makes the entire order more likely to develop eusociality, as opposed to another order of insects developing eusociality. In other words, I was trying to give a possible explaination why there are so many eusocials in Hymenoptera, as opposed to another order.

</strong>

I suspect you may be right. Other insects that have developed eusociality also have one characteristic in common: nest building.

Termites build nests, although they do not engage in a hunting/gathering lifestyle. All of the food that they require is usually part of the nest itself.

Termites do not have ploidy status as sex determination. Therefore, in termites, both sexes are workers, and both sexes are required (over a long period of time, not just for mating) for reproduction. Termites have a king, along with a queen, whereas social hymenoptera only have queens.

NPM

Non-praying Mantis

I was aware of these spiders, but spiders are not insects, and I was just mentioning eusocial insects. There are other eusocial animals, however.

From what I read about the above spiders, they appear to be subsocial. IIRC, true sociality, or "eusociality," requires at least a reproductive caste (queens) and a non-reproductive caste (workers). With those spiders, all of the members of the nest can reproduce.

Thanks for the link, though.

NPM

lpetrich

Though spiders are not true insects, they do have overall insectlike features -- size, shape, legs, etc. It's only when one looks closely that one can see the differences.

Grumpy

Yeah! And naked mole rats, too!

John R

This misses one important point.
Whether a worker dies when it stings depends on the species that they are stinging.
As I understand it, the barbs on the honeybees sting get locked in the scales on human skin, whereas other species such as frogs or cattle do not cause the sting to become wedged, and the bee is free to withdraw and sting again.