Biologists Bob Drewes and Rayna Bell searching for tadpoles of the Príncipe Giant Treefrog

Ten questions with Dr. Robert Drewes, the Academy's Curator of Herpetology.

What are some of your more remarkable discoveries?

Remarkable is in the eye of the beholder. Being in the bush and catching things is a joy. But there is nothing like the thrill of academic discovery. In the 1980s, while submerged in a swamp in coastal Kenya, I discovered a species of frog that preyed on the eggs of another species of frog. I've also worked on a species of waterproof frog. This frog exhibits almost no evaporative water loss and excretes uric acid like a bird or lizard. I discovered two species of frogs in Ethiopia that are the only terrestrial vertebrates known to be morphologically adapted for feeding on nothing but whole snails. Finding a new species is always exciting, but actually describing it is a pain.

What is your role as a scientist?

My job is to answer some basic questions: What is it? To whom is it related? Where did it come from, ancestrally speaking? What does it do?

Do you ever fear for your own safety in the field?

Africa is inherently dangerous and inherently unstable. Sure, I have some fears. But the main dangers are with people and borders. I don't much like lions or hyenas, especially at night. Yet overall, the bush is the most tranquil setting imaginable.

What's the most precarious situation you've ever been in?

I've had 38 years of adventures, including a major coup, an air raid in Zambia, and more. But adventure-wise, the first big-field expedition I did in 1969 stands out. I had received a grant from Richard Leakey, then Director of the National Museums of Kenya, to survey the Northern Frontier District. This was an area of nomadic people with few permanent towns and few water wells. We used to pay the elders to tell us where the snakes were. One old guy said, “There is a snake in a hole.” Turns out it was an old British pit lavatory left over from World War II, at least 15 feet deep. The Africans lowered me down on the end of a braided camel skin rope. And, indeed, there was a big snake down there, a spitting cobra, about six feet long. Curiously, it was described as a new species not long ago.

How did you catch it?

I caught it with a .22 rifle.

What fascinates you about reptiles and amphibians?

They are weird and wonderful. Frogs, especially, are very, very different from mammals.

Have you ever been bitten by a venomous snake?

I've been bitten a few times but they were “dry” bites. The only time I was envenomed was by a captive prairie rattler I was milking for venom studies. It rotated in my hand and nicked my finger. It hurt like hell! I iced my finger and drove to UCSF Medical Center. They kept me there for two days, so I could be observed by interns. My palm swelled to 11 inches around.

Should we be afraid of venomous snakes?

It is probably good to be aware of the venomous species in one's home area. But snakes aren't particularly aggressive or dangerous unless one is careless. The greatest number of venomous snake bites occur to the people who own them or handle them—not in the wild. Snakes are a lot more afraid of us than vice-versa.

You've been doing this for almost 40 years. What keeps you going?

The same thing that got me started: it's fun! I am way too selfish to spend my life doing something I don't enjoy. That's the bottom line!

How does snake venom work?

Snake venom is purely a food-getting mechanism. It is not a defense. It is a way of immobilizing prey. In the case of vipers and their relatives, the venom pre-digests the usually large-bodied prey from the inside. In the case of cobras, the venom is a paralytic.

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Dr. Drewes on IBSS

Dr. Drewes on IBSS

Learn more about Dr. Drewes' research, publications, and current projects by visiting the research side of our website, home to the Academy's Institute for Science and Sustainability.

Herpetology at the Academy

Herpetology at the Academy

The Academy's Herpetology collection of amphibians and reptiles is one of the 10 largest in the world, containing more than 309,000 cataloged specimens from 175 countries. Learn more about the department's staff, research, and expeditions.