Why groups form

Why groups form is a basic question in sociobiology.

Biologists recognise a number of common reasons why groups form - which include:

• Raising offspring;
• Safety in numbers;
• Hunting in packs;
• Gathering to mate;

This post will attempt to find general versions of these ideas that cover most of the reasons why groups form in nature.

1. Kin selection - Family groups are some of the most common reasons why groups form in nature. Theres a well-established theory which covers this: kin selection. My main comment here is to say that a symbiosis-aware version of kin selection theory is needed. Groups can form not because their members are kin, but because their members' symbiotic partners are kin. This idea should be taken to cover shared cultural symbionts as well.

2. Combined power - groups are often stronger and more capable than their individual members. They can do things which individuals cannot. For example, 10 ants may be able to transport a leaf which no single ant can lift. Groups are thus biology's multipliers. Groups can build bigger and better nests than individuals can. A pack of animals is can tackle larger prey than a single hunter. Similarly, a herd of animals can often mount a better joint defense against predators than a single animal can manage. Combining power does not require synergy - where the group is stronger than the sum of its component parts. Additivity (or worse) can still be enough. The term "power": is intended to refer to motor power, sensory power, compute power - or some combination of these.

3. Sharing information - groups often form in order to share information between their members. One classical way in which this hapens is the group members share their genes with other group members by having sex with them. This happens on leks for example. This is part of the reason why groups consisting of members of the same species form so frequently. We clearly need a symbiosis-aware version of this idea. Hosts may form groups not so they can have sex with each other, but so their parasites or symbionts can have sex. Indeed, it isn't just sex - groups can form so that individuals can transmit their symbionts to others who don't yet have them, or so individuals can gain symbionts from others. Cultual symbionts also need to be included. For example, when Catholic groups form, one thing that happens is that the Catholic memes get to meet and mate with other Catholic memes. Some other things happen as well - which could be characterized as "collect the full set" and "get the latest upgrades". Those with incomplete sets of Catholic memes can get new synergetic meme partners. Those with out-of-date Catholic memes can upgrade to the latest versions. A good generalized version of these ideas is to say that groups sometimes form in order to share information between group members.

I don't pretend that these ideas explain all group formation in nature. For an example of group formation which they explain poorly, consider the following article from Ed Yong (2013):

Parasites Make Their Hosts Sociable So They Get Eaten

That's a case of sharing genetic information. However, there the information involved is shared across groups, not between individuals within the group.

Group selection is sometimes cited as a force driving group formation. However, the claims of group selection advocates seem to be covered by 1 and 2 above - at least if you use a post-1975 version of kin selection theory. The claim that group selection explains things that the 1960s versions of kin selection theory cannot does not seem to be worth very much.

Though not complete, I think the above principles explain most cases of group formation. The exceptions I am aware of are not far from this framework, but near to the edge of it.

Ed Yong - Parasitic mind control

I've witten a number of articles about parasitic mind control. I have also promoted the symbiont hypothesis of eusociality. I didn't see Ed Yong's 2014 talk until now, though.

There's only a bit in the video about parasite-induced social behavior, but this is turning into a big topic in memetics.

Ed has now written a book relating to this general topic: I Contain Multitudes: The Microbes Within Us and a Grander View of Life. Here is a video of a book talk by Ed..

Daniel Dennett: Memes as the key to human intelligence

Dennett of the hijacking of the term "meme", the "De-Darwinization" of cultural evolution, memes as "virtual machines" - and various other topics.

I've previously made some critical comments regarding some of this material.

Susan Blackmore: From Memes to Tremes

Memetic dysbiosis

One piece of symbiology terminology that seems to be missing refers to the idea of host fitness being compromised by the lack of important symbionts. Connie Barlow memorably proposed that these be termed "Ghosts" in her book The Ghosts Of Evolution. Anyway, I am not going to address that issue here, but will instead discuss an umbrella category that includes these "ghosts" - dysbiosis.

Wikipedia says that "dysbiosis" is: "a term for a microbial imbalance or maladaptation on or inside the body, such as an impaired microbiota". Since the etymology of "dysbiosis" suggests that it is a symbiology term - like "symbiosis" - it ought to be a general term that can also be applied to human hosts in the context of cultural symbionts. "Maladaptation" should be taken to refer to the effect on host fitness. Of course, the dysbiosis could be adaptive from the perspective of the finess of the smaller symbionts.

From its definition, memetic dysbiosis could be the result of missing memes, bad memes - or some combination of the two. In either case, memetic dysbiosis could be addressed by some sort of meme therapy.