On a plane and in your yard

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

It’s time to talk about everybody’s least favorite subject: snakes. I live next to the jungle and have had many brown tree snakes in my house. I’m not afraid of them and to get rid of them, I just grab them and pop them into the freezer. No sharp objects, no blood, they just sleep with the frozen fishies.

I have been bitten a couple of times and am always amazed by how much it hurts when you consider the wounds aren’t very deep. There’s always a lot more blood than you’d expect from such tiny wounds too. Researchers are doing work on snake venom and have come up with some surprising results. Read on!

Researchers seeking to learn more about stroke by studying how the body responds to toxins in snake venom are releasing new findings that they hope will aid in the development of therapies for heart disease and, surprisingly, cancer.

The Japanese team is examining platelets, blood cells that control blood clotting. They’ve also discovered that platelets are involved in the development of blood vessels that feed blood to cancer tumors, as well as in forming the blood clots that cause stroke and heart attack.

What does this have to do with snake venom? Snake venom contains toxins that target the proteins in platelets. Some of them prevent the platelets from clotting (which certainly explains all the blood from the small wounds of a brown tree snake bite) and other toxins cause them to clot.

The Japanese researchers are now studying chemicals found in snake venom to see if they can use them to prevent the growth of the blood vessels that feed tumor cells. They have also found chemicals in snake venom that prevent the growth of the lymphatic vessels that allow cancer cells to enter the lymphatic system and spread throughout the body. So, thanks to these researchers, there’s a possibility that snake venom may turn out to do a body good after all!

The other thing I’ve always wondered is how brown tree snakes can climb up the walls of my house, and there’s research in that area as well. In a unique study involving young boa constrictors, University of Cincinnati researchers had snakes climb vertical ropes of various sizes and flexibility to see how they do it.

They discovered that regardless of the diameter or flexibility of the rope, the snakes alternated curving between left and right as they climbed the ropes. On thicker ropes, they could move greater portions of their bodies forward as they climbed. As the ropes became thinner and more flimsy, the snakes used more of their bodies — including their back, sides and belly — to manipulate the rope for climbing.

Although the large muscles of boa constrictors make them fairly stocky and heavy compared to other snakes, this anatomy probably increases their strength. All of the snakes gripped the ropes using a concertina mode of locomotion, which is defined by some regions of the body periodically stopping while other regions of the body extend forward. Boa constrictors are strong enough they can support their weight with a modest number of gripping regions.

Well, that may explain how they climb ropes and vines, but it still doesn’t tell me how they climb vertical walls with no legs and no suckers. I guess I’ll just have to do my own observations!

Boa constrictor climbing up a rope. How does a snake climb a vertical surface without slipping? (Credit: Bruce C. Jayne)