the literature on ground-dwelling sciurids, emphasizing
our own work on ground squirrels, but have also cited ad-
ditional relevant rodent literature. In the first part of this
chapter we explored the variety of avenues whereby social
and antipredator systems are connected, including shared
components at multiple organizational levels and means-
end relations. Components shared by social and antipreda-
tor systems include the following: (1) shared motor patterns
at the level of basic behavioral units; and at higher orga-
nizational levels, (2) the dual social and antipredator roles
of the stress-response system, (3) shared perceptual cues
with context-dependent meaning, and (4) shared utility of
knowledge of the spatial layout and nature of the resources
in the animal’s surroundings. With regard to means-end
relations between social and antipredator systems, we dis-
cussed the familiar fact that features of social behavior and
organization are means (mechanisms) for dealing with the
threat of predation. We then examined how social and anti-
predator systems can converge in form when their partici-
pants share certain properties of their relations, specifically
parity in the threat posed by each participant and extended
occupation of the same vicinity. These properties are more
typical of social relationships, but are also found in certain
predator-prey relationships, such as that between ground
squirrels and rattlesnakes. At least two advantages can be
derived from identifying such connections and similarities
between social and antipredator systems. We are reminded
that systems that are distinct functionally may share quite a
bit of causal common ground. And we can gain a better un-
derstanding of each type of system by appealing to insights
available from the other.
We completed this chapter by exploring the proximate
and ultimate processes that generate connections and simi-
larities between systems. Key themes of this section were
that (1) organisms undergo modification in multiple time
frames, both proximate (including immediate causation and
development) and ultimate (such as current effects of selec-
tion and evolutionary persistence of traits), and (2) or-
ganisms are active participants in all such changes, rather
than simply passive responders to environmental “pres-
sures” (Lewontin 2001a, 2001b). This idea, that organisms
participate actively in the changes they undergo, is founded
on three kinds of observations: (1) animals capitalize on the
resources available from their environments and their own
structure by expropriating components from existing sys-
tems for use in new functional contexts; (2) the way systems
currently work generates constraints and opportunities for
future change, in both proximate and ultimate time frames;
and (3) organismic systems not only need to meet environ-
mental demands, but also must be compatible with the
other systems that comprise the organism.316 Chapter Twenty-Six