information on conditioning in sea slugs has been applied to our under-
standing of neural mechanisms of learning in mammals.
Evolutionary evidence from fossil brains and from the diversity of
structure of real brains in living species of birds and mammals is pri-
marily a lesson about the importance of differences.This is also the
lesson from the diversity of acoustic production systems in living species.
The major uniformity that may exist with respect to musicality is in the
construction of neural networks in real brains under environmental pres-
sures.Construction of such networks by axodendritic growth of individ-
ual nerve cells and the establishment of synaptic connections among
cells may follow very similar rules in very different species of birds and
mammals.Plasticity is,therefore,a critical phenomenon for study in
living species.Fossil evidence is helpful here primarily in suggesting lin-
eages in which the amount of construction is greatest,that is,in which
most encephalization has occurred.In birds this points to crows and
parrots (cf.Pepperberg 1994).In mammals,in addition to our own
species there are,of course,other anthropoid primates including apes,
and despite difficulties in research with marine mammals,one might pay
special attention to data on large-brained cetaceans,such as the bottle-
nose dolphin (Tursiops truncatus;Schusterman,Thomas,and Wood
1986).We are likely to learn most about the diversity of acoustic expres-
sion and some features of its evolution.With respect to musical experi-
ence,we are undoubtedly restricted to what we can learn from the
human species.Of course,with the development of our ability to com-
municate with some large-brained species (Herman 1986; Savage-
Rumbaugh et al.1993),we may be able to “ask”them to describe their
experiences,much as we have been able to learn about the chimpanzee’s
theory of mind (Premack and Woodruff 1978) with tools provided by
clever experiments on animal “language.”Conclusion
There is not much question that we can develop a good understanding
of the evolution of musical expression from our knowledge of the diver-
sity of sound-generating devices in living species of birds and mammals,
from the diversity of the neural control of the operation of those devices,
and from the structure and function of the neural and sensory systems
that are involved in the analysis of auditory signals.
Prospects for an evolutionary analysis of musical experience are much
more limited.The most important of these is based on the fact that such
experience is,to a significant extent,one in which cognitive-perceptual
brain systems are involved.We have learned a good deal about the193 Paleoneurology and the Biology of Music