Overfishing Causing Jellyfish Population Boom, Research Finds

May 16, 2013 in Animals & Insects, Humans

Jellyfish populations around the world have been increasing in recent years, and several very large jellyfish blooms have been reported since the early 2000s. The cause of these, and the general population increase, has remained somewhat unclear until now though. Is it simply observation bias? Cyclic population change? Warming waters? Changing currents?

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But now, thanks to new research from the Institut de Recherche pour le Développement (IRD), the causes have become clear. The primary cause is overfishing, and with it the decline of many ecologically important species. Many significant predators of jellyfish, such as tuna and sea turtles, have seen their numbers plummet in recent years as a result of overfishing. And with their decline, jellyfish have begun to see their populations grow. But perhaps far more important than that decline, though, is the overfishing of small pelagic fish, such as sardines and herring, which are the main competitors of jellyfish.

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Did Life Originate In Brinicles? Icy Sea Stalactites Provide Environment Conducive To Emergence Of Life

May 3, 2013 in Animals & Insects, Geology & Climate

Did life on Earth originate in the almost otherworldly environments of brinicles — the icy sea stalactites that grow near the Earth’s poles? These rather strange looking tubes of ice could very possibly have been where life on the Earth originated, according to new research published in the journal Langmuir.

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Marine Reptiles, Origins In Europe? Fossil Placodont Discovered In Netherlands

March 28, 2013 in Animals & Insects, Fossils

The origin of one of the first groups of marine reptiles, the Placodonts, is now becoming clear, thanks to the new discovery of a fossil skull in the Netherlands. The 246-million-year-old skull, discovered in the region that was once the Tethys Ocean, shows that these highly specialized marine reptiles, one of the earliest saurians, very likely originated in Europe.

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The placodonts lived for about 40 million years or so in the flat coastal regions of the Tethys Ocean, from around 250 million years ago to 210 million years ago. Possessing their “trademark” crushing teeth, they fed primarily on shellfish and crustaceans, but were likely opportunistic predators as well. The distinctive features of these teeth really make them stand out in the fossil record; “the upper jaw had two rows of flattened teeth – one on the palate and one on the jawbone – while the lower jaw only had one set of teeth ideal for crushing shellfish and crustaceans.”

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Extinction, Mass Extinctions, Extinct Species, And The Ongoing 6th Great Mass Extinction

March 7, 2013 in Animals & Insects, Fossils, Humans, Plants

Extinction, is the process by which a species, genus, or family, becomes extinct, no longer existing and living in the world. It is the abolition and annihilation of something that previously existed in the world. In the case of biology, it refers specifically to the end of an evolutionary line, or a branch on the tree of life.

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The actual moment of extinction is considered to be when the last individual representative of that species or group is no longer living. But functional extinction can occur considerably earlier than that, as a result of loss of genetic diversity, range, or an ability for the group to recover and breed.

Most types of life, especially animals, are closely tied to their ecological niches and environments. With a loss of their living environment, and its accompanying species, extinction is almost inevitable for many types of life. Species diversification and emergence typically doesn’t occur in these circumstances, it usually happens within healthy ecosystems. The long-period of time that follows large extinction events when no new species emerge is referred to as a dead zone .

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Lions Rapidly Approaching Extinction, Population Fell By 2/3 In The Last 50 Years And Lost 3/4 Of Their Previous Range

December 5, 2012 in Animals & Insects

Lions are rapidly approaching extinction in many parts Africa, new research from Panthera has found. In the last 50 years they have seen their population drop to around 1/3 of its previous size, from around 100,000 in 1960, to around 32,000 today. And perhaps more importantly, they have lost an incredible 75% of their habitat in that same time period.

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Their loss of territory has been due primarily to growing human populations and deforestation, and the subsequent acquisition and conversion of lands for agriculture and other uses.

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