Two studies led by UT Southwestern researchers shed light on the biology and potential vulnerabilities of schistosomes — parasitic flatworms that cause the little-known tropical disease schistosomiasis. The findings, published online today in Science, could change the course of this disease that kills up to 250,000 people a year.
About 240 million people around the world have schistosomiasis — mostly children in Africa, Asia, and South America in populations that represent “the poorest of the poor,” says study leader James J. Collins III, Ph.D., associate professor in UTSW’s department of pharmacology.
Most of those infected survive, but those who die often suffer organ failure or parasite-induced cancer. Symptoms can be serious enough to keep people from living productive lives, Collins says.
The parasite that causes this disease has a complicated life cycle that involves stages in both freshwater snails and mammals. Dwelling in mammalian hosts’ circulatory systems, schistosomes feed
Zoologists from Trinity College Dublin, working in tropical Southeast Asia, have uncovered a modern-day example of rapid evolution in action.
The zoologists have discovered that male and female Sulawesi Babblers (Pellorneum celebense, a species of bird) have evolved to attain different sizes on small islands, and in quick-fire time. They believe this is most likely due to evolutionary pressure favouring such “dimorphism” because the birds are able to reduce competition with each other by feeding on different, scarce resources.
The research, completed with the support of the Irish Research Council and collaborators in Universitas Halu Oleo, is published today in the journal Biotropica. The research shows that the males of the Sulawesi Babbler grow to be up to 15% larger than the females — with this difference particularly marked on the smaller islands.
Fionn Ó Marcaigh, first author on the paper and a PhD Candidate in Trinity’s