The New Neotropical Companion

canopy. Fogging involves the spraying of insecticide

into the canopy of the tree and subsequently collecting

(on cloths spread on the ground) the insects and other

arthropods that drop from the tree. (Fogging was part

of the plot of a 1990 film titled Arachnophobia. D o n’t

see it if you are easily frightened by spiders.) Erwin,

sampling 19 trees, all of the species Luchea seemannii,

identified approximately 1,200 species of beetles

(including weevils) in his samples. Erwin noted that

there were about 70 tree species per hectare (2.47 ac),

and using that estimate, judged that about 13.5% (163) of

the beetles were host- specific, occurring only in Luchea.

He then calculated that perhaps as many as 11,410 host-

specific beetles could be found within a hectare (70 × 163).

He then multiplied this figure by the number of different

tree species present in the global tropics and concluded

that the potential world species richness of beetles alone

was over 8 million! Since beetles are estimated to represent

Plate 9- 3. The Canal Zone Tree Frog (Hypsiboas rufitelus) is one

of many species of tree frogs that occur in the Neotropics.

Note the enlarged toe tips, adapted to attaching to vertical

surfaces. Photo by Dennis Paulson.

Plate 9- 4. This butterfly, Creonpyge creon, belongs to a group

called the firetips. Photo by Dennis Paulson.

Plate 9- 5. Membracis bucktoni is a unique treehopper from

Amazonia. Insect diversity is amazing, as you will see when

you start to look carefully in a rain forest. Photo by Dennis

Paulson.

Plate 9- 6. This colorful insect is a leaf beetle in the family

Chrysomelidae. Just this one family in the beetles order,

Coleoptera, is thought to contain between 37,000 and 50,000

species. Add to that all the other coleopterans, and add to

that all the other insect orders, and— wow! Photo by Dennis

Paulson.

chapter 9 why are there so many species? 137