Who is the protagonist and antagonist in The Lost World?

In the novel The Lost World by Sir Arthur Conan Doyle, the protagonist is Professor George Edward Challenger. He is a highly respected paleontologist and explorer, and he organizes an expedition to the Amazon rainforest in South America to search for a rumored lost world inhabited by dinosaurs.

The antagonist of the novel is Professor Summerlee. He is a zoologist and colleague of Professor Challenger, but he is also a skeptic who does not believe in the existence of the lost world. He is portrayed as a cautious and logical man who is reluctant to accept anything that goes against his scientific knowledge.