Geoscience Reference
In-Depth Information
seasonal forest provide food for animals and humans. Insectivorous animals, such
as anteaters, and armadillos are confined to the Neotropics, while pangolins, aard-
varks, some lemurs, and marsupial possums fill these niches in the forests of Africa
and the Asian Pacific. Several mammals have developed complex stomachs or di-
gestive processes to make efficient use of a limited diet of leaves. These include
sloths of the Neotropics and langurs in Asia. Carnivores such as jaguars, panthers,
leopards, and tigers, as well as weasels, mongooses, and civets are the main preda-
tors in the forest. Large herbivorous mammals such as elephants and rhinoceroses
use the seasonal forests of Africa and Asia. Bats are a critical component of tropical
ecosystems and are abundant in the tropical seasonal forests. Bats are important
for plant pollination, seed dispersal, and insect predation.
Tropical seasonal forests share a high diversity of birds with the rainforest. Both
seasonal and regional variations in abundance and diversity of bird families are evi-
dent. Different taxa have colonized and diversified in different geographic areas.
Seasonal availability of flowers and fruit often brings migrating species of birds into
the seasonal forests from nearby rainforest, savannas, and temperate forests of the
middle latitudes.
Reptiles and amphibians are diverse but less abundant. Tropical snakes include
venomous snakes, such as vipers, pit vipers, coral snakes, and cobras, as well as
nonpoisonous snakes. Many are similar to those in the adjacent rainforest regions
or bordering savannas. Many lizards, including skinks, iguanas, geckos, chame-
leons, and monitor lizards are found in these tropical forests. Frogs, toads, and cae-
cilians are also present.
Adaptations.
Although similar animal families and genera are found within the
rainforests and seasonal forests, tropical seasonal forests contain a number of
endemic species with unique adaptations that allow them to thrive under seasonal
shifts in resources. These adaptations include local and regional migrations, changes
in patterns of activity, changes in diet, and seasonal storage of fat or food resources.
Several vertebrates move seasonally to utilize various sources of food or shelter.
For example, howler monkeys in the Neotropics will concentrate in the greener ri-
parian forests during the dry season, and move back into the forest during the rainy
season when leaves reappear. Hummingbirds move from riparian areas to dry for-
est during seasonal floral blooms, and bats move considerable distances to seek out
trees bearing flowers and fruit. Similarly, elephant movement in Africa and Asia
can be associated with seasonal availability of palatable food and water resources.
Because many plants produce flowers, fruits, and seeds during the dry season,
many animals move from adjacent habitats to take advantage of these food resour-
ces. Asian tigers will follow their prey as they move into the dry forest.
Changes in diet, activity patterns, and the timing of reproduction are additional
adaptations many animals exhibit in response to seasonal water availability. Dur-
ing the dry season, some bat species change their diet from insects to more avail-
able, moisture-rich fruits. Anteaters will change their diet from ants to termites in
