More than Kin and Less than Kind: The Evolution of Family Conflict

by Douglas W. Mock

Sibling rivalry and intergenerational conflict are not limited to human beings. Among seals and piglets, storks and burying beetles, in bird nests and beehives, from apples to humans, family conflicts can be deadly serious, determining who will survive and who will perish. When offspring compete for scarce resources, sibling rivalry kicks in automatically. Parents sometime play favorites or even kill their young. In More than Kin and Less than Kind , Douglas Mock tells us what scientists have discovered about this disturbing side of family dynamics in the natural world.

Natural selection operates primarily for the benefit of individuals (and their genes). Thus a family member may profit directly, by producing its own offspring, or indirectly, by helping close kin to reproduce. Much of the biology of family behavior rests on a simple mathematical relationship called Hamilton’s rule, which links the benefits and costs of seemingly altruistic or selfish behavior to the degree of relatedness between individuals.

Blending natural history and theoretical biology, Mock shows how Hamilton’s rule illuminates the study of family strife by throwing a spotlight on the two powerful forces―cooperation and competition―that shape all interaction in the family arena. In More than Kin and Less than Kind , he offers a rare perspective on the family as testing ground for the evolutionary limits of selfishness. When budgets are tight, close kin are often deadly rivals.

288 pages, Paperback

First published January 1, 2004

Reviews

[Kelly · Rating 5 out of 5]

This book deals primarily with the behavioral ecology of birds and the discernable patterns, causes, and manifestations of conflict within nests. It reads surprisingly well and is far more interesting than I had anticipated. Principally, the focus is on uncovering the evolutionary justification for widely occurring (but little understood) phenomena like siblicide and parent-offspring conflict.

One interesting, albeit obvious, subject that Mr. Mock touches on is the genetic disposition (as codified by evolution) for infants to use deceit to overstate their true physiological needs. It's easy to see in infantile begging: parents are better served by reacting to certain types of false alarms because the potential cost of not doing so could prove enormous, and the children take advantage of this when competing against their nestmates for resources. Interestingly, the fight for resources such as it is is continuous, brutal, and often independent of the whether such resources are scarce or plentiful. As such, the preconditioned propensity toward dishonesty comes to characterize competition itself.

I couldn't help but notice that there are similarities in the way American Robins (as discussed in this book) and American Humans behave in this respect. More importantly, I think it's helpful to recognize that there are thousands of precedents in the natural world for behaviors that we routinely label as "evil" in our own species; particularly with respect to competitive conflicts. When individuals or groups act in seemingly irrational ways in response to competition from other groups, we are quick to find fault in cultural differences, an absence of competent leadership, or a flawed "moral universe." Things might make more sense if we stick with assessing one another as we really are: animals.

[Addendum: There's some wicked data on the black stork and infanticide that is worth the price of the book in itself.]

[Yanick Punter · Rating 4 out of 5]

Have to reread this!