SCIENCE REPORTER, MAY 2014 8

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ZEBRA STRIPES COMBAT BITING FLIES?H��� bi� ng fl ies led to the evolu� on of black and white stripes on zebras? A research team led by the University of California, Davis, seems

to believe so and has published its fi ndings in the April 1 issue of the online journal Nature Communica� ons.

The scien� sts found that bi� ng fl ies, including

horsefl ies and tsetse fl ies, are the evolu� onary driver for

zebra’s stripes. Experimental work had previously shown

that such fl ies tend to avoid black-and-white striped

surfaces, but many other hypotheses for zebra stripes have

been proposed since Alfred Russel Wallace and Charles

Darwin debated the problem 120 years ago.

These include:

1. A form of camoufl age

2. Disrup� ng predatory a/ ack by visually confusing

carnivores3. A mechanism of heat management

4. Having a social func� on

5. Avoiding ectoparasite a/ ack, such as from bi� ng fl ies

The team mapped the geographic distribu� ons of the

seven diff erent species of zebras, horses and asses, and

of their subspecies, no� ng the thickness, loca� ons, and

intensity of their stripes on several parts of their bodies.

Their next step was to compare these animals’ geographic

ranges with diff erent variables, including woodland areas, ranges of large predators, temperature, and the geographic distribu� on of

glossinid (tsetse fl ies) and tabanid (horsefl ies) bi� ng fl ies. They then examined where the striped animals and these variables overlapped.

A7 er analyzing the fi ve hypotheses, the scien� sts ruled out all but one: avoiding blood-sucking fl ies.

“Again and again, there was greater striping on areas of the body in those parts of the world where there was more annoyance from

bi� ng fl ies,” said lead author Tim Caro, a UC Davis professor of wildlife biology.

While the distribu� on of tsetse fl ies in Africa is well known, the researchers did not have maps of tabanids (horsefl ies, deer fl ies).

Instead, they mapped loca� ons of the best breeding condi� ons for tabanids, crea� ng an environmental proxy for their distribu� ons. They

found that striping is highly associated with several consecu� ve months of ideal condi� ons for tabanid reproduc� on.

Why would zebras evolve to have stripes whereas other hooved mammals did not? The study found that, unlike other African

hooved mammals living in the same areas as zebras, zebra hair is shorter than the mouthpart length of bi� ng fl ies, so zebras

may be par� cularly suscep� ble to annoyance by bi� ng fl ies.

But why do bi� ng fl ies avoid striped surfaces? Time for more research?

(Courtesy: www.sciencedaily.com)

A model Biofuel Park with 116300 Jatropha curcas plants has been established at the Defence Ins� tute of Bio-Energy Research (DIBER), a cons� tuent Ins� tute of the Defence Research & D evelopment Organisa� on (DRDO) at the Harsola (100 hectare) Military

MODEL BIOFUEL PARKFarm, Mhow. The park was set up in 2007 as part of R&D ac� vi� es under the DRDO-Army Bio-diesel Programme.

The Jatropha curcas plant starts full fruit and seed produc� on a7 er fi ve year of planta� on. The Biofuel Park started yielding good fruit and seed yield from 2012. During

the last year good fruit yield (13.41 tons of fresh Jatropha fruits) was recorded. This produc� on will increase in the years to come and DIBER will be able to produce more bio-diesel out of Jatropha seeds which will be useful in conduc� ng trials in Defence vehicles. Various trials are being conducted to enhance

Diber Biofuel Park at DIBER Project Site, Military Farm, Mhow Jatropha fruit produc� on at DIBER Project Site, Mhow

SCIENCE REPORTER, MAY 20149

SPECTRUM

CUTANEOUS LEISHMANIASIS IN RAMPUR

BUSHAHR: LACK OF AWARENESS COULD

BE DANGEROUS

L�������� is one of the most diverse and complex of

all vector-borne diseases causing signifi cant morbidity and

mortality in Africa, Asia and La� n America. It is caused by an

intracellular protozoan parasite of genus Leishmania. The

disease is endemic in 88 countries in fi ve con� nents with a

total of 350 million people at risk and annually 12 million

cases are reported.

The parasite is transmi/ ed by the bite of infected female

sandfl ies, which breed in organic wastes such as faeces,

manure, rodent burrows, leaf li/ er and in dark corners in

the crevices of walls having high humidity and temperature.

Because of their small dimensions, they can get through

standard mosquito nets.

Leishmaniasis is found in three clinical forms: Cutaneous leishmaniasis o7 en involves only the skin, and may be characterized by

one to dozens of lesions; Mucocutaneous leishmaniasis involves extensive disfi guring of the nasal septum, lips, and palate, and Visceral

leishmaniasis, also known as kala azar, is characterized by the malfunc� on of liver, spleen and bone marrow.

Cutaneous leishmaniasis is usually painless unless the lesions become secondarily infected, and except in the ear, the ulcers tend

to remain confi ned to the skin and do not aff ect the subcutaneous � ssues. Most skin lesions heal spontaneously; however, the speed

of healing varies with the species of Leishmania. In some cases, it may take several months to a year or longer. Some forms leave

permanent scars.

In India, Cutaneous leishmaniasis is endemic in Himachal Pradesh including Rampur Bushahr in Shimla district, some parts of

Kinnaur district and Nirmand and in some places in the Thar Desert of Rajasthan, bordering Pakistan.

In Himachal Pradesh there are only two hospitals that provide eff ec� ve treatment of Cutaneous leishmaniasis, one of which is very

far i.e., around 120 km from the area where it is endemic. The Mahatma Gandhi Medical Services Complex, Khaneri, Rampur Bushahr,

district Shimla is the only hospital in this area where successful treatment is provided to pa� ents. Around 200 to 300 cases of Cutaneous

leishmaniasis are treated each year in this hospital free of cost under the Na� onal Vector Borne Disease Control Programme.

Recent molecular studies have shown that the causa� ve agent of cutaneous leishmaniasis in this area is Leishmania donovani

which usually causes visceral leishmaniasis in humans. Although there are hundreds of cases reported each year, residents of Rampur

Bushahr and the neighbouring areas are not aware of the disease. Most people consider it a normal wound or injury. Some pa� ents

suff ering from Cutaneous leishmaniasis had been visi� ng private clinics and applying ointments on the lesions. Some were taking

an� bio� cs prescribed by doctors in the local dispensary.

In September 2013 eff orts were made to make people aware through posters in Hindi explaining the causes, symptoms

and cure of Cutaneous leishmaniasis. There is also need for sustained campaigns or seminars in local schools and colleges of

Rampur Bushahr to make students aware of this disease who can then transmit this informa� on to others.

Contributed by Arushdeep Sidana, Ph.D. Student, Molecular and Immuno-parasitology Laboratory, Shoolini University, Solan, H.P.;

Email:

the fruit and seed yield of Jatropha in the Biofuel Park.

For maximum u� liza� on of the land of the Biofuel Park, Camelina sa� va, another high oil yielding crop, is being grown as

intercropping in Jatropha planta� on during winters when the Jatropha plants shed leaves and the plant remains naked and hence will

not hinder sunlight penetra� on and crop produc� on.

Contributed by Dr Ranjit Singh, Scientist, Defence Institute of Bio-Energy Research (DIBER) Project Site, Mhow (MP)-453441, Email: sangwanranjit@rediffmail.com; Shri Umesh Singh Scientist, DIBER Project Site, Mhow, and Dr Mohd. Naseem, Director, DIBER, Haldwani (UK)-263139

Camelina as intercrop in Jatropha planta� on

In India, Cutaneous

leishmaniasis is endemic in

Himachal Pradesh including

Rampur Bushahr in Shimla

district, some parts of

Kinnaur district and Nirmand

and in some places in the

Thar Desert of Rajasthan,

bordering Pakistan.

SCIENCE REPORTER, MAY 2014 10SCICISCIENCENCENCENCE RE RE RE REPOEPOEPOEPORTERTERTERTERRRR AYMAYMAYMAY 202020141414 10101010

SPEC

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M ASTRONAUTS’ HEARTS TURN SPHERICAL IN SPACE

A study of 12 astronauts, presented at the American College of Cardiology’s 63rd Annual Scien� fi c Session, shows the heart becomes

more spherical when exposed to long periods of microgravity in space, a change that could lead to cardiac problems.

With implica� ons for an eventual manned

mission to Mars, the fi ndings represent an important

step toward understanding how a spacefl ight of 18

months or more could aff ect astronauts’ heart health.

“The heart doesn’t work as hard in space, which

can cause a loss of muscle mass,” said James Thomas,

M.D., Moore Chair of Cardiovascular Imaging and Lead

Scien� st for Ultrasound at NASA, and senior author of

the study. “That can have serious consequences a7 er

the return to Earth, so we’re looking into whether

there are measures that can be taken to prevent or

counteract that loss.”

The researchers say that knowing the amount

and type of exercise astronauts need to perform to

keep the heart healthy is going to be very important to

guarantee their safety on a long fl ight like a mission to

Mars. Thomas adds that exercise regimens developed

for astronauts could also be used to help maintain

heart health in people on Earth who have severe

physical limita� ons, such as people on extended bed rest or those with heart failure.

The research team trained astronauts to take images of their hearts using ultrasound machines installed on the Interna� onal Space

Sta� on. Twelve astronauts par� cipated, providing data on heart shape before, during and a7 er spacefl ight.

The results show the heart in space becomes more spherical by a factor of 9.4 percent. The astronauts’ more spherical heart shape

appears to be temporary, with the heart returning to its normal elongated shape shortly a7 er the return to Earth. The more spherical

shape experienced in space may mean the heart is performing less effi ciently, although the long-term health eff ects of the shape change

are not known.Spacefl ight is known to cause a variety of cardiac eff ects. Upon return to Earth, astronauts commonly become lightheaded

or pass out in a condi� on known as orthosta� c hypotension, in which the body experiences a sudden drop in blood pressure

when standing up. Arrhythmias have also been observed during space travel, and there is concern that the radia� on

astronauts are exposed to in space may accelerate atherosclerosis. The research team is con� nuing to examine these

and other poten� al cardiovascular eff ects.

(Courtesy: www.sciencedaily.com)

P���������� insects play an important role in forest and agro ecosystem. Ironically, in recent decades nectarivorous bees are de-clining at an alarming rate and, surprisingly, in parts of south India, it has been observed that one of the reasons is due to abandoned disposable cups.

Chandrasekaran et al. (2011) reported that increased awareness about environment phased out glass cups and other metal cups from tea and coff ee stalls in several areas of Tamilnadu. The usage of disposable paper cups in coff ee/tea shops and juice stalls in ur-ban, semi-urban, rural and eco-tourism spots and protected areas in Tamilnadu, is common now.

Remnants of sugary residue in the aban-doned cups a/ ract the honey bees. Instead of visi� ng natural fl owers, the bees fi nd an al-terna� ve food source in these cups. However, these cups act as ‘death traps’ for them be-

cause they fall into the cups and are unable to come out and fl y, which results in large-scale mortality. The researchers reported the death of nearly 168 bees every day from a single shop and reported 25,211 dead bees in the coff ee bars in their study area within 30 days.

We have also found that the dammar bees or s� ngless bee, Melipona iridipennis (Meliporidae), an important pollinator, also get a/ racted by disposable cups. Within ten minutes of our observa� on we found nearly 48 bees lost their lives in a single cup – we found more than 800 bees in a single dust bin placed before a tea shop on the same day (8-hour observa� on). If the trend con� nues for a few days or weeks the workers in the en� re colony will lose their lives.

The honey and wax produced by the dammar bees play an important role in the livelihood of the poor forest-dwelling com-muni� es in the Nilgiri Biosphere Reserve

(NBR) where 15 local ethnic groups harvest honey as a source of revenue (Keystone Founda� on 2001).

Loss of nectarivore bees would re-sult in the signifi cant plumme� ng of forest agro diversity resul� ng in skyrocke� ng food prices. Moreover many fl oral species are dependent on honey bees for pollina� on and many local communi� es also depend on honey and wax as a source of livelihood (Thomas et al., 2009).

An immediate ban or safe way of dis-posing the cups is needed. Using closed type dustbin and frequent and periodical cleaning of the bins is necessary to prevent large-scale mortality of bees.

Contributed by S. Sandilyan, PG and Research Department of Wildlife Biology and Zoology, A.V.C. College, Mannampandal-609305, May-iladuthurai, Tamilnadu; Email: ssandilyan@gmail.com

DISPOSABLE PAPER CUPS – THREAT TO HONEY BEES IN SOUTHERN INDIA

SCIENCE REPORTER, MAY 201411 SCISCISCIENCENCENCE RE RE REPOEPOEPORTERTERTERRR MAYMAYMAY 20202014414111111

FRESHWATER CRABS – HIDDEN PROMISE

SPECTRUM

I� Punjab, U arakhand, U.P., Himachal Pradesh and Jammu & Kashmir where freshwater is the only source of aqua c fauna, people mostly rely on fi shes as a source of food. However, besides fi shes, freshwater bodies also hold crabs, which are a rich source of proteins, omega fa y acids, amino acids. People who live near streams are also aware of their medicinal importance.

In J&K, freshwater crabs inhabit the Jammu region because of its poikilothermic nature that restricts its distribu on in the Kashmir region where the season is cold throughout the year. Compared to marine crabs, freshwater crabs are smaller in size. Freshwater crabs can be seasonal breeders or annual breeders. However, unlike marine crabs, the development is direct in freshwater crabs – eggs hatch into crablets rather than larvae.

In Jammu region, freshwater crabs such as Maydelliathelphusa masoniana as well as Himalayan potomon are found in the stream of Gho-manhasan and Ta diyal (tributaries of river

Chenab) and Jajjar and Ban Ganga stream, respec vely. The life cycle of freshwater crabs is quite vulnerable to physico-chemical parameters, which can restrict their popula on. Being more vulnerable to aqua c pollu on, freshwater crabs also act as biological indicators.

In Gho-manhasan, due to increase in pollu on and over-exploita on by the locals their number have shown dras c decline. Fishermen o1 en poison the stream leading to mass mortality of the aqua c fauna including fi shes and crabs. Similar is the case in the Ta diyal stream. The lower reaches of Ban Ganga, which receive enough waste material from Gulshan Langar as well as from the upper reaches, the number of crabs

exhibits a remarkable decrease. Recently, due to construc on of a new road near Jajjar stream as well as dumping of wastes in the stream, the number of freshwater crabs Himalayan potamon has been reduced considerably.

Freshwater crabs are one of the most beau ful creatures among the aqua c fauna. They can be kept in aquariums like ornamental fi shes because of their beau ful colours. The crabs have medicinal values – the exoskeleton is used to obtain chi n and chitosan that can be drawn in sheets to form an oxidant medicinal bo les as well as to prepare medicines.

However, most people are s ll unaware of their economic importance as well as the food value of freshwater crabs, due to which it s ll remains an untouched source of food that can subs tute fi shes. It can even open job opportuni es for the people of the state by aquaculturing of these crabs.

Clockwise from top left: Freshwater crabs in water; Freshwater crab on land; Parental care shown by the female by carrying eggs in its abdomen.

Contributed by Rakesh Kumar Gupta, Research Scholar, Department of Zoology, University of Jammu, Jammu, J&K-180006; Email: rakeshgupta174@gmail.com

Freshwater crabs can be seasonal breeders or annual breeders. However, unlike marine crabs, the development is direct in freshwater crabs – eggs hatch into crablets rather than larvae.

Freshwater crabs are one of the most beautiful creatures among the aquatic fauna. They can be kept in aquariums like ornamental fi shes.