The orca, or killer whale (Orcinus orca), is a curious combination of fearsome predator and charismatic marine mammal. These large, black-and-white members of the dolphin family live in all the ...

Steve Nix is a member of the Society of American Foresters and a former forest resources analyst for the state of Alabama. Cottonwoods are poplars native to North America, Europe, and western Asia.

Melissa Breyer was Treehugger’s senior editorial director before moving to Martha Stewart. Her writing and photography have been featured in The New York Times, The Guardian, National Geographic, ...

Steve Nix is a member of the Society of American Foresters and a former forest resources analyst for the state of Alabama. Leaf shapes play an important role in tree identification, providing key ...

Doris Lin is an animal rights attorney and the Director of Legal and Government Affairs for the Animal Protection League of New Jersey. Her focuses as an expert writer include animal rights and ...