Lianas

Photo Gallery: Lianas

All liana photos by Stefan Schnitzer, Liana Expert

Stefan is a friend of ours at the University of Pittsburgh, who runs the field data collection for Dr. Walt Carson's project on the effects of insects and mammals on forest vegetation-- how much do they feed on and what does it do to the open-ness of the vegetation. Stefan works part of the year on BCI and on the nearby peninsula of Gigante. He has a very interesting lifestyle. Here are his comments, and his own photos of lianas in Panama at his study site. Notice how complicated the tangles of lianas can be! Try to imagine searching for a silky anteater (tapicara) in all these vines:

liana tree

liana tree

liana tree

liana tree

Photo Credit: Stefan Schnitzer

What do you do as a scientist?

Before I answer that, let me ask you a few questions. Did you ever wonder how tropical forests grow? How do they stay as forests and not turn into grasslands or fields? Do trees live forever? What happens when a tree getsold and falls over? What grows in that fallen tree's spot? Well, as a scientist, my job is to answer questions like these. My main interests are in learning how tropical forests grow and why there are so many species of trees and lianas in tropical forests.

So how do tropical forests grow?

Most of the time, after a tree falls, little trees that are growing in the shadows of the big trees will grow up and take-over the spot of the fallen tree. But what I have found is that sometimes the little trees can't grow because they are strangled by lianas!

What are lianas?

Lianas are vines that are woody, like trees. But unlike trees, lianas can't stand-up on their own. They have to climb-up trees to get to the sunlight. Lianas are really neat plants and they are all over tropical forests, twisting and twining around the trees. But sometimes lianas twist around the
trees so much that they strangle the trees! When lianas strangle the little trees that are trying to grow-up under the fallen trees, parts of the forest can actually stop growing. Instead of new trees, the forest can become a big tangle of vines!

How long do lianas live?

How long do lianas live??? How many grains of sand are there on the beach? How many drops of water are there in the ocean? How many angels can dance on the head of a pin? When we know the answer to these questions, we may know the answer to How Long Do Lianas Live. Actually, this is a great question! All we know is that lianas live a long, long time, probably many times longer than trees. How do they do this? Well, my theory is that lianas are superorganisms that slowly move through time and space. When a large liana, which can be over a kilometer in ength and many hundreds of years old, falls from the canopy with a treefall, it will often stay alive and send out new branches that climb back up to the canopy. These new branches develop their own roots and each branch effectively becomes a new individual. These new individuals, although the cells are young, are really a part of the old liana that originally fell from the canopy. Therefore, some lianas, even though they may look young, may be thousands, or tens of thousands of years old! But until I get around to testing this theory, we don't really know how long lianas live. Another unanswered mystery of the rainforest!

Why is it important to know how tropical forests grow?

Scientists want to understand how tropical forests grow because we want to know how the natural world works. Understanding the natural world is important for a number of reasons. First, knowing how plants and animals have evolved and coexist give us an idea of how the natural world works and our place, as humans, in that world. Second, human beings are having a huge impact on the world, and we are destroying tropical forests faster than ever before. If we ever hope to re-grow tropical forests we will need to know how they grow naturally.

How did you become a scientist?

I wasn't always a biologist. After I graduated from college I took a job writing computer programs with a computer company. But I realized that I didn't want to work in an office; I was more interested in learning about biology and the natural world. So I went back to school to study biology.
In addition to learning about biology, I found that school is a lot more fun when you are interested in what you are learning.

Do you have any advice for kids who want to become scientists?

Yes, I think that the best scientists are ones that are curious and imaginative. If you are interested in learning how things works and you have curiosity and imagination then you have the potential to become a scientist.