Lek: a group of male animals that have gathered to show off to females.
Mutualism: an interaction between two organisms that benefits both of them. Sometimes one of the two organisms lives and multiplies into the other one, which is called the host.
Sexual reproduction: when two organisms join their genetic material (often eggs and sperm) to make a new organism.
The rainforest is home to lots of species of animals. So many different animals live here that by looking at the rainforest, we have a chance to study adaptations and interactions that may not be found anywhere else.
Humans and plants have an interesting relationship—we depend on plants for food, for some medicines, and for decoration and even stress relief, if we have houseplants. However, some ants that live in the rainforest have even more complex, or involved, relationships with plants.
Leafcutter ants are little farmers in the rainforest. They cut pieces of leaves off of plants and carry them into storage spaces underground. Here, the ants use the leaf chunks as food to feed another organism—a fungus.
They grow this fungus to feed baby ants, called larvae. The fungus depends on the ants to bring them food, and the ants depend on the fungus to help ant larvae grow. This type of relationship, in which both species benefit, is called mutualism.
Like ants, some frogs in the rainforest depend on plants to help their babies, or young, grow. Colorful frogs called poison dart frogs depend on tiny pockets of water that gather in the leaves or branching stems of certain plants, especially epiphytes.
After their eggs hatch into tadpoles, the parent frogs move the tadpoles into these water pockets. If a pool runs out of food, or if the water level gets too low, the poison dart frog will carry the tadpoles on its back to a new plant with a larger pocket of water.
These devoted parents may also lay eggs that have no young tadpoles as food for their young.
Though relationships between different species in the rainforest can be interesting, the most amazing things you see in the rainforest are sometimes between a male and female of the same animal species. When some animals are looking to reproduce, or have babies, they need to attract another animal with which they can mate. Oftentimes, in species that have sexual reproduction, it is the male that tries to attract a female.
Some males attract females with amazing dances or colors, using tricks to try to show off for, or impress, a female. The cock-of-the-rock, a type of bird that lives in the undergrowth of the forest, has males with bright red and black color patterns. Five to 20 of these bright males fly, dance and call together in a group called a lek. These birds dance in a small area to try to attract one of the dull-colored females.
When a female arrives at the dancing grounds, the males dance and call even harder. Even with up to 20 males calling, only one male wins out—usually the brightest, the loudest, or the best dancer.
With all the different bright display colors of some animals, the dark, shadowy, green rainforest can be transformed into a beautiful show of moving colors.
Images via Wikimedia commons. Additional image by USFW.
Karla Moeller. (2013, July 24). Animals of the Rainforest. ASU - Ask A Biologist. Retrieved September 23, 2022 from https://askabiologist.asu.edu/animals-rainforest
Karla Moeller. "Animals of the Rainforest". ASU - Ask A Biologist. 24 July, 2013. https://askabiologist.asu.edu/animals-rainforest
Karla Moeller. "Animals of the Rainforest". ASU - Ask A Biologist. 24 Jul 2013. ASU - Ask A Biologist, Web. 23 Sep 2022. https://askabiologist.asu.edu/animals-rainforest
The rainforest holds all kinds of exotic animals, like this ocelot.