Stories tagged Interdependence of Life

Feb
21
2005

One of the ongoing debates in science is: where the heck did birds come from? Bird bones are fragile and don't often become fossils, so there's not a lot of evidence. And when a new bird fossil is found, there's always a lot of debate over how it fits into the puzzle.

Feb
04
2005

Researchers at the Mayo Clinic have found a way to use measles to fight cancer.

Viruses are parasites. To reproduce, they seek out sites on a healthy cell, get inside, and then take over the host's cellular machinery. For years, researchers dreamed of using viruses to hijack cancer cells.

The Mayo team knew that measles kills most cancer cells, too. But to use the virus as an anti-cancer treatment, they had to change the virus so it wouldn't attack healthy cells. They eliminated the virus's ability to bind to its natural receptors, and retargeted it to zero in on ovarian cancer cells.

In lab animals implanted with human cancer cells, the virus hunted down and destroyed only infected cells. Clinical trials on patients with ovarian cancer began last summer, but it will be at least three years before the treatment is approved for use in hospitals.

Jan
14
2005

In August 1995, schoolchildren found deformed frogs in a wetland near Henderson, Minnesota. Some frogs had extra legs, others no legs at all. Some had missing or extra eyes, toes, or feet. And some also had problems with their internal organs. By the fall of 1996, there were over 200 reports of freakish frogs, from two-thirds of Minnesota's counties. Deformed frogs have since been found in 44 states.

Deformed frog: This frog has two right back legs. Others have been found with missing legs, missing parts of legs, or legs in unexpected places.
Deformed frog: This frog has two right back legs. Others have been found with missing legs, missing parts of legs, or legs in unexpected places.Courtesy Minnesota Pollution Control Agency

A 1997 study raised frogs in the lab, mixing pure water with water from two Minnesota sites that had lots of deformed frogs. The more pond water that was used, the more likely the lab frogs were to be deformed. Water from sites with healthy frogs produced healthy animals in the lab. The scientific conclusion was, "There's something in the water." But what could it be? Since then, several researchers have been hunting for the cause.

Scientists have proposed several explanations for the deformities. It may be parasites, chemicals, ultraviolet light, or some combination of the three. Lab studies have shown that all of these factors, alone or in combination, can cause some deformities. But no single cause seems to explain it all. The research doesn't yet add up to a neat and tidy answer, so scientists continue to puzzle out the story.

Who cares about frogs? You should. If there's something wrong with the water, it may eventually hurt all of us. But it will hurt frogs first. Frogs have thin skins, and easily absorb any contaminants in the water. Frogs seem to be in trouble all around the world. There are more and more reports of deformities. And some species have disappeared, or no longer live in their old habitats. It's a wide-spread problem that may affect us all.