Read morePrevious studies had found that microbes could thrive at the boundary where oil and water meet in nature, helping to break down the oil. However, investigators had thought oil was too toxic for life, and that the levels of any water inside the oil were below the threshold for life on Earth.
“Oil was considered to be dead,"said lead study author Rainer Meckenstock, an environmental microbiologist at Helmholtz Zentrum München in Germany.
Now scientists have found microbes active within Pitch Lake, dwelling inside water droplets as small as 1 microliter, about one-fiftieth the size of an average drop of water. "Each of these water droplets basically contains a little mini-ecosystem,"study co-author Dirk Schulze-Makuch, an astrobiologist at Washington State University in Pullman, told Live Science.
These droplets contain a diverse group of microbial species that are breaking the oil down into a variety of organic molecules. The chemistry of the droplets suggests this water does not come from rain, but from ancient seawater, or brine from deep underground.
ecology
Read moreSir John added: “There is a real problem of ignorance. There is a false assumption that what is good for mammals is good for everything else, or at least not harmful. People assume that vultures belong in the Serengeti with the lions, but they are common in Spain and France; a wild vulture has even been seen in Holland.
There was a Black Vulture spotted in Wales, but they think it escaped from somewhere. Vultures have always been disregarded because of the way they look, but actually they do a very, very good job.”
José Tavares, director of the Swiss-based Vulture Conservation Foundation, added: “Vultures fulfill an incredibly important role. They clean the countryside, they provide an ecological service that is free and unique. In a few depressed areas of Europe, they bring tourist income. If diclophenac becomes widespread in Europe, carcasses would have to be collected and incinerated at huge cost.“
Read moreUniversity of Canterbury ecologist Professor Jason Tylianakis says no study has explicitly tested whether exotic species fill the roles left by declining native species.
“A collaborative research project between scientists at the University of Canterbury and the University of Oviedo, Spain, has examined the role of exotic birds in dispersing the seeds of native New Zealand trees and shrubs.
“Many fruiting plants require birds to carry their seeds to new locations and drive the persistence and recovery of native forests.
“New Zealand fruit-feeding birds have historically suffered a strong decline but the country has also gained new fruit-eaters in the form of introduced European birds, such as blackbirds and song thrushes.’’
The Canterbury researchers studied the network of feeding interactions between different species of plants and birds in the North and South islands. They found that the intermediate body and beak size of exotic birds allowed them to feed on a great variety of different fruits.
This allowed the birds to disperse seeds of plant species that were not eaten by native birds at any given location and helped to stabilise seed dispersal across a whole range of plants.
Without introduced species, many native plants would not have their fruits eaten and their seeds would simply fall to the ground below the tree.
Another Canterbury biological sciences researcher, Dr Daniel Stouffer, says exotic species were less discriminating in their fruit consumption patterns.
“Native fruit-eaters have developed strong affinities for or against consumption of native fruit species making our native communities vulnerable to loss of key bird species. However, the exotic species are more than happy to make equal use of all the fruits available, thereby spreading their benefit more widely.’’
Professor Tylianakis says people often consider invasions by non-native species as always being harmful.
“However, many of our native species have already become extinct and sometimes we need new species to fill their role. Although they often do harm, we can’t always assume that non-native species are the bad guys in our constantly changing eco-systems,” Professor Tylianakis says.
These species were not just ornaments of the natural world. The new work presented at the conference suggests that they shaped the rest of the ecosystem. In Britain during the last interglacial period, elephants, rhinos and other great beasts maintained a mosaic of habitats: a mixture of closed canopy forest, open forest, glade and sward. In Australia, the sudden flush of vegetation that followed the loss of large herbivores caused stacks of leaf litter to build up, which became the rainforests’ pyre: fires (natural or manmade) soon transformed these lush places into dry forest and scrub.
In the Amazon and other regions, large herbivores moved nutrients from rich soils to poor ones, radically altering plant growth. One controversial paper suggests that the eradication of the monsters of the Americas caused such a sharp loss of atmospheric methane (generated in their guts) that it could have triggered the short ice age which began about 12,800 years ago, called the Younger Dryas.
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Journal of a Cosmic Anthropologist 