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Andrena Gravida is the name of a wild bee declining in the United Kingdom and the Netherlands. A {{U}}(31) {{/U}} of months ago the recent drop in migratory bird populations was known, based on a study {{U}}(32) {{/U}} in the Netherlands. Now there's more troubling news from that part of the world: a study released today by the journal Science reports that there's been a dramatic loss of {{U}}(33) {{/U}} among wild bees over the past 25 years in Holland.
There's {{U}}(34) {{/U}} to a 70% decline in the variety and {{U}}(35) {{/U}} of bee {{U}}(36) {{/U}} in some areas in Britain. A loss of biodiversity is more subtle {{U}}(37) {{/U}} an overall drop in absolute numbers of {{U}}(38) {{/U}} or plants, but it's still {{U}}(39) {{/U}} a problem because the {{U}}(40) {{/U}} species in an ecosystem, the more the system {{U}}(41) {{/U}} on each one of them, and if disease or some other {{U}}(42) {{/U}} wipes out a species, its function could go unfilled. In the {{U}}(43) {{/U}} of bees, that {{U}}(44) {{/U}} is to pollinate plants, both wild and crop plants. And {{U}}(45) {{/U}} the authors of the study show, there's been a {{U}}(46) {{/U}} decline in plants that were once pollinated {{U}}(47) {{/U}} the disappearing bees. Indeed, it isn't clear {{U}}(48) {{/U}} came first, the plant decline or the decline in bees. It's also not clear {{U}}(49) {{/U}} any crops are in trouble, only that there's a potential for it if this trend continues. It's also not clear {{U}}(50) {{/U}} it's happening. Climatic changes caused by global warming are a possibility, but so is the destruction of wild habitat in both countries, as population and industry both expand.
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