The kind of biologist who would most likely study interactions between organisms is an ecologist.

Here's why:

* Ecology is the branch of biology that focuses on the interactions between organisms and their environment. This includes interactions with other organisms, such as competition, predation, symbiosis, and more.

* Other biologists might study aspects of these interactions, but ecologists specialize in understanding the complex relationships between organisms and their environment.

Let me know if you have any other questions about biologists!