News / Africa

Human Health Depends on Biodiversity

Multimedia

Audio
Joe DeCapua

There’s a good reason why people should be concerned about having a healthy environment containing lots of animal and plant species. A new study says the loss of biodiversity may make humans more vulnerable to infectious diseases.

Biodiversity is one of the ways to measure the health of an eco-system.   And the healthier an eco-system is, the better off we are.  That’s because animals, plants and even microbes can act as a buffer between people and pathogens.

Associate Professor Felicia Keesing, an ecologist at Bard College in Annandale, New York, is the lead author of the study.

“Biodiversity is the diversity of genes, species and eco-systems that occupy the earth.  Most of the time when we talk about biodiversity, we mean the diversity of species,” she says.

Keesing says the study adds a new reason to protect the environment.

“People have always recognized that there’s some sort of esthetic value in having all of these different creatures living on earth with us.  Many people feel that there’s an ethical responsibility to protect them.  But in the last couple of decades, scientists have begun to document ways in which biodiversity is actually providing services to us.  Such services become practical reasons for protecting biodiversity as well,” she says.

It’s long been known that biodiversity helps provide clean water, cycles nutrients through the eco-system, and absorbs carbon from the atmosphere.  But Keesing says the fact that biodiversity protects humans from disease is a compelling reason for conservation.

Sucking up pathogens

Keesing says, “What we’ve seen over and over again in different studies that we describe in our paper is that in diverse systems the species that are present either reduce the number of disease bearing organisms by competing with them.  Or they suck up pathogens, sort of vacuum up pathogens, and then don’t transmit them again.”

That protection suffers as biodiversity is lost.  Keesing says one example is Lyme Disease, which is a common tick-borne bacterial illness in the United States.

“If you have a low diversity system, the species that are present always include white footed mice.  And white footed mice are very, very good at transmitting the Lyme bacterium back out so that humans are at risk,” she says.

Eco-systems under attack

Biodiversity faces many threats all over the world.  The biggest, she says, is land conversion.

“We’re destroying habitats,” she says, “So there are fewer places for organisms to live.  But there are also a lot of other threats.  The key ones are also climate change.  So as the climate changes species are struggling and in some cases going extinct because they can’t adapt quickly enough – or they have nowhere to go that has the appropriate environmental conditions.”

Other threats to biodiversity include the spread of invasive species of plants and animals, as well as overhunting or overharvesting of species.

“In many ways, the biggest threat is that all of these things are happening at the same time and interacting with each other,” she says.

Keesing rejects the idea that the loss of biodiversity is simply a matter of survival of the fittest, with humans being the most fit.

“Our survival,” she says, “is actually linked to the survival of these other species.  So, neither our short term nor our long term survival prospects are increased because we’re destroying other species.”

Scientists are also considering what a loss of biodiversity means for such diseases as Ebola in Africa.  In other words, could it mean the disease could become more common and spread to new areas if there’s a weak biodiversity buffer?

The Bard College associate professor says the effects of biodiversity loss are so clear, there’s no reason to delay protecting the Earth’s eco-systems.

You May Like

DRC Tries Mega-Farms to Feed Population

Park at Boukanga Lonzo currently has 5,000 hectares under cultivation, crops stretching as far as eye can see, and is start of ambitious large-scale agriculture plan More

Video Survivor Video Testimonies Recount Horrors of Guatemalan Genocide

During a conflict that spanned more than three decades, tens of thousands of indigenous Mayans were killed More

Video War, Drought Threaten Iraq's Marshlands

Areas are spawning ground for Gulf fisheries, a resting place for migrating wildfowl, source of livelihood for fishermen and herders who have called the marshes home for generations More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Nobel Prize Winner Malala Talks to VOAi
X
August 31, 2015 2:17 AM
Nobel Peace Prize winner Malala Yousafzai met with VOA's Deewa service in Washington Sunday to talk about women’s rights and unveil a trailer for her new documentary. VOA's Katherine Gypson has more.
Video

Video Nobel Prize Winner Malala Talks to VOA

Nobel Peace Prize winner Malala Yousafzai met with VOA's Deewa service in Washington Sunday to talk about women’s rights and unveil a trailer for her new documentary. VOA's Katherine Gypson has more.
Video

Video War, Drought Threaten Iraq's Marshlands

Iraq's southern wetlands are in crisis. These areas are the spawning ground for Gulf fisheries, a resting place for migrating wildfowl, and source of livelihood for fishermen and herders. Faith Lapidus has more.
Video

Video Colombians Flee Venezuela as Border Crisis Escalates

Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Rebuilding New Orleans' Music Scene

Ten years after Hurricane Katrina inundated New Orleans, threatening to wash away its vibrant musical heritage along with its neighborhoods, the beat goes on. As Bronwyn Benito and Faith Lapidus report, a Musicians' Village is preserving the city's unique sound.
Video

Video In Russia, Auto Industry in Tailspin

Industry insiders say country relies too heavily on imports as inflation cuts too many consumers out of the market. Daniel Schearf has more from Moscow.
Video

Video Scientist Calls Use of Fetal Tissue in Medical Research Essential

An anti-abortion group responsible for secret recordings of workers at a women's health care organization claims the workers shown are offering baby parts for sale, a charge the organization strongly denies. While the selling of fetal tissue is against the law in the United States, abortion and the use of donated fetal tissue for medical research are both legal. VOA’s Julie Taboh reports.
Video

Video Next to Iran, Climate at Forefront of Obama Agenda

President Barack Obama this week announced new initiatives aimed at making it easier for Americans to access renewable energy sources such as solar and wind. Obama is not slowing down when it comes to pushing through climate change measures, an issue he says is the greatest threat to the country’s national security. VOA correspondent Aru Pande has more from the White House.
Video

Video Arctic Draws International Competition for Oil

A new geopolitical “Great Game” is underway in earth’s northernmost region, the Arctic, where Russia has claimed a large area for resource development and President Barack Obama recently approved Shell Oil Company’s test-drilling project in an area under U.S. control. Greg Flakus reports.
Video

Video Philippine Maritime Police: Chinese Fishermen a Threat to Country’s Security

China and the Philippines both claim maritime rights in the South China Sea.  That includes the right to fish in those waters. Jason Strother reports on how the Philippines is catching Chinese nationals it says are illegal poachers. He has the story from Palawan province.
Video

Video China's Spratly Island Building Said to Light Up the Night 'Like A City'

Southeast Asian countries claim China has illegally seized territory in the Spratly islands. It is especially a concern for a Philippine mayor who says Beijing is occupying parts of his municipality. Jason Strother reports from the capital of Palawan province, Puerto Princesa.
Video

Video Ages-old Ice Reveals Secrets of Climate Change

Ice caps don't just exist at the world's poles. There are also tropical ice caps, and the largest sits atop the Peruvian Andes - but it is melting, quickly, and may be gone within the next 20 years. George Putic reports scientists are now rushing to take samples to get at the valuable information about climate change locked in the ice.

VOA Blogs