Month: July 2018

Massive fruit trees in the Thailand evergreen forest need massive herbivores to help spread their seeds, according to a new study.

Based on the diets and habits of mammals, scientists found that elephants are the best allies for the Thai Annonaceae tree to spread its seeds.

In the diverse environment of Khao Yai National Park, there is a complex set of relationships between the plants and animals. Not every species of fruiting tree is an attractive meal to all herbivores. A team of researchers, led by Kim McConkey from the University of Nottingham, set out to study one particular tree, the Platymitra macrocarpa from the family of custard apple trees.

The p. macrocarpa produces 3-to-5-inch fruit that are ripe from May through August. McConkey tracked how often animals visited the trees and ate the fruit, including elephants, bears, monkeys, gibbons and Sambar deer. They measured the animals’ fruit consumption as well as the ensuing seed dispersal and seed viability.

Researchers found the seeds in the dung of some species while others like the Sambar deer regurgitated the large seeds. When asked about tracking animal poop, McConkey admitted, “I’ve got two boys so they just love what I do.”

As expected, the Asian elephants were the major seed dispersers for the p. macrocarpa. Elephants aren’t often seen in the area of the trees McConkey studied, but as she told VOA, “I thought if I’m going to see them feed on any fruit, it’s going to be this one.” Her hunch was borne out in the data, with elephants consuming only 3 percent of the fruit but producing 37 percent of the viable seedlings.

These findings regarding the Asian elephants point to the important role they play in the ecosystem. Jedediah Brodie, chair of conservation in the Wildlife Biology Program at the University of Montana, told VOA that “overhunting in the tropics often drives large animals locally extinct but leaves smaller species like rodents. And this study shows that those smaller animals just are not able to replicate the ecological role of the larger species.”

When looking at the performance of other species, the researchers were surprised by how effective Sambar deer were at dispersing seeds. “Sambar deer generally have quite a bad rap in these forests,” McConkey said. “People think they’re seed predators, but it turns out they actually do disperse a lot of seeds.” While the Sambar deer weren’t quite as effective seed dispersers as gibbons (21 percent), they still produced a respectable 17 percent.

Bruchid beetles were the primary challenge to producing viable seedlings. The beetles, which are known to infest all kinds of seeds and beans, spoiled most of the seeds left exposed on the forest floor. Unlike the regurgitated seeds of the sambar deer, the seeds went through the elephants’ digestive system and were covered by excrement. The seeds were protected from beetles and provided with an effective, natural fertilizer and were able to survive and grow into seedlings.

It is easy to think of animals adapting to their environment through evolution and behavioral change, but we rarely consider the same relationship in the opposite direction. The massive Platymitra macrocarpa has perhaps evolved to provide fruit that appeals to more than one frugivore.

As McConkey told VOA, “The husk of the fruit — it’s like the outer covering of the fruit — has become very thick, and it’s that outer covering that deer eat. But if you open up the fruit, each seed is covered by this juicy, soft pulp, and it’s that that the monkeys and gibbons like.” She thinks that this might be a case where the tree evolved to appeal to multiple animal species to increase the chance of spreading viable seeds.

Despite the variety of animals eating the seeds, elephants are still the tree’s best chance of producing viable seedlings. When asked what might happen if elephants were to disappear from the region, Brodie responded, “That’s the million-dollar question.”

This research is published in PLOS ONE.
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Japan on Wednesday approved its first national legislation banning smoking inside public facilities, but the watered-down measure excludes many restaurants and bars and is seen by critics as toothless.

The legislation aims to lower secondhand smoking risks ahead of the 2020 Tokyo Olympics amid international calls for a smoke-free event. But ruling party lawmakers with strong ties to the tobacco and restaurant industries opted for a weakened version.

The upper house approved and enacted the bill into law Wednesday after it was approved earlier by the lower house.

Last month, Tokyo separately enacted a stricter ordinance banning smoking at all eateries that have employees, to protect them from secondhand smoke. The ordinance will cover about 84 percent of Tokyo restaurants and bars.

But the law still allows many exceptions and the Tokyo Games may not be fully smoke-free.

Japan often has been called a smokers’ paradise. Until now it has had no binding law controlling secondhand smoke and ranked among the least protected countries by the World Health Organization. That has brought pressure from international Olympic officials. 

The new national law bans indoor smoking at schools, hospitals and government offices. Smoking will be allowed at existing small eateries, including those with less than 100 square meters (1,076 square feet) of customer space, which includes more than half of Japanese establishments. Larger and new eateries must limit smoking to designated rooms.

Violators can face fines of up to 300,000 yen ($2,700) for smokers and up to 500,000 yen ($4,500) for facility managers.

The law will be implemented in phases through April 2020. 

​’Too lenient’

The law allowing smoking at more than half of Japan’s restaurants as exceptions is inadequate, said Hiroyasu Muramatsu, a doctor serving on Tokyo’s anti-smoking committee. “The law is too lenient compared to international standards,” he told Japan’s NHK public television. “We need a full smoking ban.”

The health ministry’s initial draft bill called for stricter measures but faced opposition from lawmakers sympathetic to the restaurant industry. The government also was viewed as opposed to harsher measures because the former monopoly Japan Tobacco is still partly state-owned.

In Japan, almost a fifth of adults still smoke. The rate for men in their 30s to 50s is nearly twice as high, according to a government survey last year.

Most office workers now light up only in smoking rooms or outdoors, and cities are gradually imposing limits on outdoor smoking in public areas. But most restaurants and bars in Japan allow smoking, making them the most common public source of secondhand smoke. 

“Secondhand smoking has been largely considered an issue of the manners, but it’s not,” Kazuo Hasegawa, 47, a nonsmoker who has developed lung cancer, told NHK. “It’s about health hazards. It harms people. And I don’t want younger generations to have to suffer like me.”

In Japan, about 15,000 people, mainly women and children, die annually as a result of secondhand smoke, according to government and WHO estimates. 

 
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The world is close to eliminating the threat from polio, but to eradicate the disease, it must be eliminated everywhere. Health officials say that’s the tricky part, because if the virus responsible for the crippling disease exists anywhere, it can still spread worldwide. Sadie Witkowski reports on the challenges that face polio eradication efforts.
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The move to end polio started in 1985 with Rotary International. At that time, polio paralyzed hundreds of thousands of children every year. There is still no cure, but two scientists developed vaccines against the virus in the 1950’s. 

Dr. Jonas Salk produced one with an inactivated virus that could protect against polio without spreading the disease. Later, Dr. Albert Sabin developed an oral vaccine with weakened strains of the virus. 

In 1988, public and private groups joined the effort in the Global Polio Eradication Program. Members included governments, the World Health Organization, the United Nations Children’s Fund (UNICEF), Rotary International, the U.S. Centers for Disease Control and Prevention (CDC) and the Bill and Melinda Gates Foundation. 

Since then, the number of polio cases has dropped by 99.9 percent. Last year, 22 children were crippled by this disease. The wild polio virus exists in only three countries: Pakistan, Afghanistan and Nigeria, but it’s still a global threat.

Dr. John Vertefeuille, from the CDC said, “This last mile is a complicated mile.” It’s not just because of conflict or terrorism. “It’s extreme remoteness. It’s very fragile health systems.” And in these remote conflict prone areas gaining access to children can be a major problem. 

If polio exists anywhere, it can once again spread everywhere. 

Vertefeuille and other experts discussed strategies to realize a polio-free world July 10 at the Center for Strategic and International Studies in Washington. 

Widespread unrest in Afghanistan has kept thousands of children from receiving polio vaccines this year. Conflict in northern Nigeria does the same. 

What’s more, the border between Afghanistan and Pakistan stretches for more than 2,000 kilometers. Thousands of people who cross this very porous border can easily transmit the virus in both countries.

While the funding and technical support has to come from large, private-public partnerships, immunization teams succeed best if they are local. Approaches have to take culture and customs into consideration. 

In many places the vaccinators are women because women can go into the homes, talk to other women and gain access to the children. 

Elsewhere, soldiers vaccinate children when they take over an area run by anti-government forces. Vaccination teams have to be prepared to move quickly when there is a lull in the fighting and to deliver multiple doses of vaccine in a short period of time.

Surveillance is just as critical. To end polio, you have to know where the outbreaks are. Community volunteers are a great resource. Some get cell phones so they can alert health officials if a child becomes paralyzed. 

Another challenge is getting children in migrant groups vaccinated. Vertefeuille says this is where technology helps. The CDC uses satellites to see where people have moved and what areas are abandoned. Clues are where structures have been repaired, where the grass grows on roads, indicating abandoned areas, and where it doesn’t, indicating where people are living. 

Dr. Andrew Etsana from the International Federation of Red Cross and Red Crescent Societies said these groups present a particular challenge because “you have people moving with a virus and it is difficult to track them and vaccinate the vulnerable children in this mobile population.”

Another issue is the nature of viruses themselves. Viruses mutate. So far, the polio vaccines have been effective, but if not enough children get vaccinated, the virus can change, and perhaps make the vaccine less effective. That’s why every child needs to be vaccinated. 

Outbreaks that can be avoided by vaccinating the whole population so that there are no gaps for the mutated virus to slip through. 

International experts are working with local leaders to close this gap. 

Another issue is complacency. Etsana said, “People are getting tired. The program has been going on. They thought it would have ended.” 

Rotary has pledged to continue its support, other groups as well. International support and funding is critical to ending polio, but after three decades, many people have never seen polio. Etsana says he sees complacency creeping into all areas of the program. “The funders of the program are also getting tired. The fund is drying up and if the fund dries up and the job is not done, we’re going to have a major problem. We may have reinfection.” 

But, if people recognize the program’s value – it has united communities, established vaccine centers, created partnerships never before imagined – the world can not only end polio, but tackle other diseases as well. The polio program is widely credited with stopping the spread of Ebola in Nigeria while the disease ravaged other west African countries.

 
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