Organisms and P...

An investigator went to Central America to study oropendolas, which are communal nesting birds. Another species of bird, the cowbird, sometimes lay its eggs in the nests of oropendolas. Some of the populations of oropendolas throw the cowbird eggs out of the nest, and some don't. The investigator was interested in finding out why some birds would raise other species as their own but others would toss them out. By watching the nests closely, he found that blowflies lay their eggs in the nests of oropendolas and that the young larvae, maggots, feed on the young birds. If young cowbirds are in the nest, the precocious cowbirds eat the blowfly larvae, protecting the young oropendolas. In colonies of oropendolas that discriminate against cowbirds, throwing them from the nest, the blowflies are not eaten by cowbirds. These colonies of oropendolas build their nests close to a particular wasp colony, and the wasps eat the blowflies.
The relationship between the oropendolas and the cowbirds is 

The greatest number of thorns per plant are found in 

Choose the correct statement that best explains the data.

What relationship between two populations can you reasonably deduce when comparing curves I and II?

The best explanation for the change in the distribution of Chthamalus observed $$3$$ months after removal of the larger Balanus individuals is that

A fungus that lives symbiotically with plants is

Competition between the members of a woodchuck population in a large field is increased by the increase in

An investigator went to Central America to study oropendulas, which are communal nesting birds. Another species of bird, the cowbird, sometimes lay its eggs in the nests of oropendulas. Some of the populations of oropendulas throw the cowbird eggs out of the nest, and some dont. The investigator was interested in finding out why some birds would raise other species as their own but others would toss them out. By watching the nests closely, he found that blowflies lay their eggs in the nests of oropendulas, and that the young larvae, maggots, feed on the young birds. If young cowbirds are in the nest, the precocious cowbirds eat the blowfly larvae, protecting the young oropendulas. In colonies of oropendulas that discriminate against cowbirds, throwing them from the nest, the blowflies are not eaten by cowbirds. These colonies of oropendulas build their nests close to a particular wasp colony, and the wasps eat the blowflies.
The relationship between the oropendulas that discriminate against cowbirds and the cowbirds is one of

Large number of eggs are produced by a spider species but due to little parental care, only a few of them reach adulthood. The line representing the survivorship curve for this species is

The origin of the predation ability of Venus flytraps is explained by