(Heliconius sp.; plate 4- 20). There is much to be learned
about this diverse group of lepidopterans, known
sometimes as longwing butterflies, and we will say
much more about them in chapter 11.
We notice something on the bark of a nearby tree.
Is it merely a feature of the bark? No, it’s yet another
butterfly, perched head down on the tree trunk. It is
one of the cracker species (Hamadryas spp.; plate 4-
21), of which there are several that are highly similar
in appearance). Also called calico butterflies, they
range widely from the southern United States through
Amazonia. Not all are cryptically colored.
We begin to notice the quiet. Rain forests often
seem serene, especially toward midday and into the
afternoon hours. Birdsong has seemingly ceased
entirely. Insect stridulations continue, and about the
only other sound to be heard is of leaves rustling in the
light wind at canopy level. But there are still things to
be discovered. A loud, sharp rapping alerts us to the
activity of a woodpecker. We see it, getting a good look
at a female Lineated Woodpecker (Dryocopus lineatus;
plate 4- 22), one of the most widely distributed of the
Neotropical woodpeckers.
Looking into the understory, we spot something. It’s
a small animal, and it is looking back at us, its long tail
hanging limply below it. Is it some form of squirrel? A
binocular view reveals that it is a monkey, a Geoffroy’s
Tamarin (Saguinus geoffroyi; plate 4- 23), a small
monkey species common to Panama and Colombia.
Unlike the larger capuchins, spider monkeys, woolly
monkeys, and howler monkeys, tamarins (along with
marmosets and saki monkeys) lack a prehensile tail,
so they do not wrap their tails around tree limbs, using
them as a fifth appendage. Monkeys are a major subject
of chapter 16 and are also discussed elsewhere in the
book.
There are sounds, bird sounds. We have encountered
an understory flock of various species traveling through
the forest together as they collectively search for prey.
For a few minutes they seem to surround us, and before
they move on through the understory, we see a few
pretty well. In the silence that follows, we pause for a few
minutes and scan the forest around us, from low to high,
looking for more birds (plates 4- 24– 27).
The trail has brought us out to an open area, a large
forest gap (chapter 7), where it seems suddenly much
hotter, especially with the accompanying high humidity.
Some bright flowers are evident at the edge of the gap,
a cluster of heliconias (plate 4- 28). Sitting on a smallPlate 4- 22. This female Lineated Woodpecker pauses to stretch
her right wing while hitching up a tree in search of insect
grubs or ants. Photo by John Kricher.Plate 4- 23. A Geoffroy’s Tamarin studies us as we study it.
Photo by John Kricher.chapter 4 finding animals in rain forest 65