to deposit an unfertilized egg to serve as food for the
developing frog.
Poison- dart frogs (Dendrobatidae) are the most
colorful, and dangerous, of the tree frogs (plates 11- 21–
24). Some are shiny black with red or orange markings,
some bright green. Indigenous people utilize the
poisonous alkaloids from the frogs’ skins in making
potent darts for hunting. The poison affects nerves and
muscles, producing paralysis and respiratory failure.
These colorful frogs hunt by day, feeding on termites
and ants, and it has been suggested that their warning
coloration evolved in response to their long feeding
periods, when they would otherwise be vulnerable
to predators. Poison- dart frogs are discussed in more
detail in chapter 11.
Glass frogs are small green tree frogs, most with
transparent belly skin that reveals the beating heart
and intestinal system (plate 16- 89). They attach eggs
to leaves over streams, and larvae hatch and drop into
the water. Eggs tend to hatch in heavy rain, facilitating
the release of tadpoles into the water below. Tadpoles
become bright red and burrow in stagnant litter in slow
pools. Their color is the result of a concentrated blood
supply, an adaptation to low oxygen levels in the mud.Typical Frogs
Numerous species of typical frogs inhabit swamps,
marshes, wet forests, and other suitable habitats
throughout the Neotropics. The genus Leptodactylus
(plate 16- 90) is well represented by about 75 species,
but there are many others as well.Toads
The Cane Toad (Rhinella marina [Bufo marinus];
discussed in chapter 11; plate 11- 31), largest of the
New World anurans, is common in many areas of the
Neotropics and has become a pest species in southern
Florida and Australia. It secretes irritating fluid from its
skin and is toxic if eaten. The large, nearly softball- size
animal would make a tempting target for predators, but
its toxic integument is so dangerous that dogs and cats
have reportedly died just from picking up the toad in
their mouths. One curious human application of toad
toxin has been studied in Haiti. Along with extract
from puffer fish and two plant species, toad toxin is
used to induce the deathlike trance observed in victims
of voodoo rituals.Plate 16- 89. Fleischmann’s Glass Frog (Hyalinobatrachium
fleischmanni) calling on a leaf. Photo by James Adams.Plate 16- 88. Red- eyed Tree Frog. Photo by Steve Bird.Plate 16- 90. Savage’s Thin- toed Frog (Leptodactylus savagei) is
one of many species of its genus. It occurs in much of Central
America and in northern South America. Photo by Dennis
Paulson.chapter 16 from monkeys to tarantulas: endless eccentricities 357