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A group of dolphins living off the coast of Australia apparently teach their offspring to protect their snouts with sponges while foraging for food in the sea floor. Researchers say it appears to be a cultural behaviour passed on from mother to daughter, a first for animals of this type, although such learning has been seen in other species.

The dolphins, living in Shark Bay, Western Australia, use conically shaped whole sponges that they tear off the bottom, said Michael Kruetzen, lead author of a report on the dolphins in Tuesday's issue of Proceedings of the National Academy of Science. "Cultural evolution, including tool use, is not only found in humans and our closest relatives, the primates, but also in animals that are evolutionally quite distant from us. This convergent evolution is what is so fascinating," said Kruetzen. Researchers suspect the sponges help the foraging dolphins avoid getting stung by stonefish and other critters that hide in the sandy sea bottom, just as a gardener might wear gloves to protect the hands.

Kruetzen and colleagues analyzed 13 "spongers" and 172 "non-spongers" and concluded that the practice seems to be passed along family lines, primarily from mothers to daughters. "Teaching requires close observation by the pupil," Kruetzen said. "Offspring spend up to four years before they are weaned, so they would have ample time to observe their mum doing it - if she is a sponger."

"This study provides convincing evidence that the behaviour is transmitted via social learning," commented Laela Sayigh of the University of North Carolina Center for Marine Science. "Such social learning appears to be widespread among the Shark Bay dolphins," said Sayigh, who was not part of Kruetzen's team. Only one male was observed using a sponge. Kruetzen noted that, as adults, male and female dolphins have very different lifestyles. Adult males form small groups of two or three individuals that chase females in reproductive condition, he explained. "I would think that they do not have time to engage in such a time-consuming foraging activity as adults, as they are busy herding females." Currently at the University of Zurich, Switzerland, Kruetzen was at the University of New South Wales, Australia, when the research was conducted. The work was funded by the Australian Research Council, the National Geographic Society, the WV Scott Foundation and the Linnaean Society of New South Wales.

Bumblebees act like copycats, following another bee's lead when foraging for food in unfamiliar flowers, according to a study in this week's issue of the journal Current Biology. This study of the “bumblebee mind” may offer insight into the survival and growth of plant species which depend on bees for pollination.

Bee social interactions, such as “bee dances”, are among the most complex systems of communication in the animal kingdom. Though social animals at times, bumblebees had been considered loners when it came to finding nectar. “People had thought of them as individual foragers. No one had thought they'd attract one another to the food source,” said the study's lead author, biologist Ellouise Leadbeater of the University of London.

Leadbeater and her colleagues studied 17 pairs of bees. For each pair, they released one bee into a clear box containing a single group of three identical, artificial flowers. Once this “demonstrator” bee had settled upon the blossoms, which offered a delicious dose of sugar water, seven other groups of sweetened fake flowers were placed in the box. Faced now with eight groups of flowers from which to choose, four each of yellow and blue hue, a second “observer” bee was released into the chamber.

The observers initially preferred the same group of flowers on which the demonstrator had already begun feasting. But this mimicking only occurred when the bees explored unfamiliar flowers. After experiencing the taste of a flower during their first flight, almost two thirds of the observers simply returned to the same color flower when the test was repeated. But observers who dared try a different color only landed on the new color if the demonstrator was already on that same color, with the great majority landing on the exact same group that was occupied by the demonstrator.

Bumblebees mark flowers they visit with scented secretions that repel other bees, allowing them to focus their efforts on untouched flowers likely to offer greater reward. The finding that bees sometimes seek, rather than avoid, such deflowered flowers invites speculation as to the advantage of such behaviour. Given limited resources with which to forage among unknown flowers, bees may be driven to invest in a flower-type that's already been shown to reward another bee.

“Bees are making these decisions millions of times each day. How they make these decisions effects which plants get visited and which don't,” and thus which get pollinated, Leadbeater said

It was an odd life. I was pushing a wheelbarrow, with an injured pelican in it. My day consisted of feeding the chimps, checking to see if the birds had suffered any injuries, and reprimanding the gibbon that had escaped from its cage. I was a volunteer at the local zoo. The days are full of adventure. On the first day, Ruby, the female chimpanzee decided to hurl her steel mug at me as I assisted in the morning feeding. The second day, I had to wade into the water, tuck a pelican under my arm and take it to the hospital, watching out for its long beak that was sharper than a knife. This was hard work, sometimes dangerous and at first a lot of dirty work as well. But those days gave me a great insight into the lives of not just the animals but the human beings at the zoo.

I spent my mornings with the zoo keepers, cleaning out the cages and filling the earthen bowls with water, as the animals lazed around in the winter sun. At the back of my mind I was acutely aware of the jackal that paced up and down in its cage, the lioness who spent over 48 hours in a tiled cage, and the hoolock gibbon that spent all its time alone, moping. These were bored, depressed animals. A complex set of problems plague zoos in India. By addressing behavioural abnormalities in the animals and alleviating stress through enrichment of the environment they live in their lives can be improved. Environmental enrichment through simple measures like hanging of baskets, planting of trees, can be undertaken. Food can be hidden in different parts of the enclosure so that the animal spends time foraging for food and spends less time resting.

Animals, especially primates, are very social animals but are often housed alone. This practice may be convenient from the point of view of the management but is extremely detrimental from the point of view of the psychological well being of the animal.

Surplus animals in zoos create several problems in terms of management and inbreeding. For example in the Delhi Zoo, all the lions cannot be released into the outside enclosure at the same time, as they will fight. This means an animal spends more than 24 hours indoors in a cage, which increases stress levels.

Even if enclosures are large enough, their design may be such that they create stress as animals have little private space to hide from visitors. Hiding spaces can be created so that the animal has the option of being out of public view if it so desires. Mixed species exhibits can be encouraged especially with species that are naturally sympatric in the wild. This not only encourages natural behaviour but is also a good educative tool. The above measures do not require much infrastructure or funds. What they do require is sound knowledge of the animal's natural behaviour and the ability to recreate that in the captive environment of the zoo. During my stint of volunteering at the zoo, I felt the person who was crucial to the well being of the animal was the keeper. In western countries, the keeper is trained in animal management and is at least a graduate. In India, most keepers are barely educated and their role is mostly confined to cleaning and sweeping the cages.

The real change in Indian zoos will come about only when keepers take a keen interest in the animals, and the management of the zoos gives scope for it. Perhaps what is needed is more young people to be trained and who are willing to work with the animals. Maybe then, zoos can make a real contribution to preserving biodiversity.

In India there are as many as 58 zoos across the country that house thousands of birds, animals and reptiles. Zoos in our country are frequented by people from all walks of life and in many instances provide the only contact that they have with wildlife. Visitors shouting, throwing stones and pulling animal's tail not only increases the stress levels of the captive animals but often harm them. "Friends of Zoos", volunteers can be recruited to keep in check the crowds, ensure that animals are not disturbed when sleeping or being fed.

For almost a decade now, zoos have been changing from being zoological gardens to large naturalistic spaces. Zoos have copied enclosure designs from each other, using larger open habitats and model exhibits and have learnt from experiences of the animal habitat in the wild. The question asked commonly is since animals are happy and healthy in zoos, is there a need to protect them in national parks and sanctuaries as well?

Zoo animals often are healthier and live longer than their wild counterparts since they are freed from the need to look for food and shelter, always be wary of predators and provided treatment for illness and injury.

It is true that captive animals have less freedom of choice in terms of movement. Though animals in the wild have freedom of movement, many species enforce their own limitations through territorial behaviour, marked by scents and availability of food.

Though the debate of whether animals in the wild are happier than those in captivity will always be stuck on the larger question of imposing human values on them, today through a scientifically based plan of naturalistic habitat design it is possible and constitutes an essential component of well being in zoo animals.

Animals and their habitats are inseparable and normal levels of general activity and foraging are encouraged. Designs in zoos have to take into account animal and human behaviours.

To understand this concept we need to place the animal in a dominant position. When the lion is inside a cage, the humans outside are dominant. When we are in a cage, the animal outside is dominant. If I was walking through the Gir sanctuary at night, the barriers between the lions and me are not clearly defined and the lion is in a dominant position. Landscaping and designing are, therefore, important. The barrier between the animal and the view should be invisible and generate enough excitement for the viewer.

Often people throw things at the animals, complaining they are not exhibiting proper "animal like behaviour". Zoos can be seen as a theatre or stage cleverly built and serving the important purpose of showing people that they and the forest are no longer inseparable and that if they respect the animal they will be welcome.

Zoos are common to Species Survival Plans and are increasingly important to save biodiversity. Contrary to the dictionary meaning of zoos, our Wildlife Protection Act refers to the zoo as an establishment, whether stationary or mobile, where animals are kept for exhibition to the public. The recent amendment also includes circuses. Modern zoos are more cooperative, organised and highly professional institutions than before.

Recently the Jersey Wildlife Preservation Trust changed its name to Durrel Wildlife Preservation Trust. Many American zoos have added the term "Botanical Gardens" to their names recognising the importance of landscape and habitat.

In India, the Nehru Zoological Park embodies many principles of global trends with regard to their large naturalistic exhibits with emphasis on native regional species.

The modern zoo is a place where quality is more important than quantity. Natural exhibits encountered in the wilderness benefits people and make zoos a lot more fun.

This is certainly significant as globally zoos, Botanical Gardens and Aquariums host more than 300 to 400 million visitors each year. Thus they provide meaningful education and recreation apart from conservation and research.