Readers already familiar with previous editions of A
Neotropical Companion will immediately understand
the tone and objectives of this book. This edition is not
written in an academic style, even more deliberately so
than its predecessor. Most important, it is not about how
to identify various plants and animals of the tropics. When
I visited Antarctica a few years ago I brought with me a
book that illustrated literally every species of mammal
and bird I was likely to find in Antarctica (mostly, of
course, in the waters around the continental landmass).
I had but to match the animal with its picture and bingo,
a name! I saw most of the species listed. I did not have to
worry about reptiles and amphibians, as there are none in
Antarctica. The insects are few to none as well. But that
is because Antarctica is very cold and windy, a basically
inhospitable place to terrestrial life in general.
Not so with the tropics.
Consider birds, for example, a group with which I
have considerable familiarity. On my Antarctica trip I
saw almost all of the bird species present, and the list
was fewer than 50 species. If I told you there are nearly
350 species to be found in the Neotropics, and you
compared that with the number of Antarctic bird species,
you would quickly see why it would take a much bigger
book to cover just the bird species of the Neotropics, to
say nothing of mammals and other animal groups. But
in reality, there are nearly 350 species of hummingbirds
(family Trochilidae) alone in the Neotropics. Several
other bird families (Furnariidae, the ovenbirds and
woodcreepers), Tyrannidae (the tyrant flycatchers),
and Thraupidae (tanagers and related species) have
similarly high species richness. Add to those all the
other bird species, and you have about one- third of the
world’s approximately 10,000 bird species, present and
accounted for in Central and South America, most of
them in either the Andes or the Amazon regions. So it
becomes immediately obvious that it would take many
volumes to catalog each and every bird, mammal,
reptile, and amphibian species of the region. Add insects
and other invertebrates, whose diversities are in the
high thousands (likely well over a million), and it soon
becomes hopeless to generate any sort of comprehensive
field guide to the identification of Neotropical animals.
Just to thoroughly catalog the butterflies of the relatively
small country of Costa Rica, for example, requires two
thick volumes. The distribution and identification of
birds found in Ecuador, another small country, also
requires two volumes.
And consider plant species. If you visit the lush
cove forests of the central Appalachians, such as those
found in Great Smoky Mountains National Park, you
can, with skill and patience, find about 25 to 35 tree
species in a single tract of 2 hectares, or about 5 acres
of forest. (Note: hereafter in this book, we’ll use the
abbreviations ha for hectares and ac for acres.) Take
that numerical range, multiply it by 10, and you get the
picture for parts of Amazonia. That’s right, more than
300 tree species may be present in just 2 ha. And many
of them look very similar, requiring expert training in
tree identification techniques. It is thus obvious that
no book purporting to discuss the general ecology and
natural history of the Neotropics could possibly focus
on identification of each and every species.
The good news is that you do not by any stretch of
the imagination have to be competent in identifying
all of the trees, birds, or bugs in order to comprehend,
appreciate, understand, and enjoy what you are seeing
and experiencing as you walk a rain forest trail. Of
course some degree of identification knowledge is
very useful: Is that a howler monkey or a capuchin? Is
that a toucan or a parrot? Is that tree a legume? Is that
flower a heliconia? Thus I have selected to illustrate
and discuss examples of widespread organisms that
tend to be consistently encountered in many places
throughout the Neotropics.
There are two words to keep in mind as I accompany
you through the pages of this book: observation and
interpretation. I have learned to see the world through
the eyes of an ecologist, to “read” the landscape, to
“see and comprehend” interactions among species.
Ecologists typically identify patterns in nature
that serve as initial jumping- off points that lead to
investigative science. One global pattern, for example,
is the distribution of species groups, such as trees,
mammals, birds, and beetles. By far the majority
of species from these various groups are found in
equatorial regions, and species numbers (measured
in units of area, such as number of breeding species
per hectare) decline sharply as you move away from
equatorial regions. Polar regions, the most inhospitable
of terrestrial environments, have the fewest species
(recall the Antarctica example above). This is a broad
and consistent pattern, one that interested Charles
Darwin (he talks about it in his most famous book, On
the Origin of Species). Ecologists try to learn what the
factors are that force such patterns, the causal factors.How to Use This Book
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