Discovery of diamonds in small rock sample hints at possibility of new deposits in area similar to world’s richest gold mine in South Africa — ScienceDaily

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The presence of diamonds in an outcrop atop an unrealized gold deposit in Canada’s Far North mirrors the association found above the world’s richest gold mine, according to University of Alberta research that fills in blanks about the thermal conditions of Earth’s crust three billion years ago.

“The diamonds we have found so far are small and not economic, but they occur in ancient sediments that are an exact analog of the world’s biggest gold deposit — the Witwatersrand Goldfields of South Africa, which has produced more than 40 per cent of the gold ever mined on Earth,” said Graham Pearson, researcher in the Faculty of Science and Canada Excellence Research Chair Laureate in Arctic Resources.

“Diamonds and gold are very strange bedfellows. They hardly ever appear in the same rock, so this new find may help to sweeten the attractiveness of the original gold discovery if we can find more diamonds.”

Pearson explained that ex-N.W.T. Geological Survey scientist Val Jackson alerted his group to an unusual outcropping on the Arctic coast that has close similarities to the Witwatersrand gold deposits.

Pearson said this outcrop of rocks, known as conglomerates, are basically the erosion product of old mountain chains that get deposited in braided river channels.

“They’re high-energy deposits that are good at carrying gold, and they’re good at carrying diamonds,” he said. “Our feeling was if the analogies are that close, then maybe there are diamonds in the Nunavut conglomerate also.”

Pearson said finding new diamond deposits in Canada’s North is critical in Canada continuing to host a $2.5-billion-per-year diamond mining industry.

So, on a hunch, Pearson used the last of his Canada Excellence Research Chair funding that brought him to the U of A, along with funding from the Metal Earth Project and the National Science Foundation, and

Recent findings suggest the repeated evolution of similar traits in island lizards was not channelled by developmental responses to the environment, as commonly thought — ScienceDaily

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Scientists have challenged a popular theory behind the evolution of similar traits in island lizards, in a study published recently in eLife.

The findings in Greater Antillean Anolis lizards provide insights on why creatures often evolve similar physical features independently when living in similar habitats. They suggest that the role of developmental plasticity in shaping adaptive evolution may be less important than commonly thought.

Developmental plasticity refers to how development responds to the environment, in particular the way that an organism’s genetic constitution (or genotype) interacts with its environment during development to produce a particular set of characteristics (or phenotype).

“Anolis lizards that live on all four of the Greater Antillean islands have independently and repeatedly evolved six different body types for maneuvering through their given habitat,” says lead author Nathalie Feiner, Researcher at the Department of Biology, Lund University, Sweden. “As a result, they make a great model for studying why evolution often repeats itself.”

To address this question, Feiner and the team used micro computed tomography scans to measure the shoulder, hip and leg bones of 95 species of anoles that live on the Greater Antillean islands. Their work revealed that several of the species’ body shapes evolved along similar trajectories.

“These body shapes are adapted by natural selection, but several different shapes could in principle perform equally well in a given habitat,” says senior author Tobias Uller, Professor of Evolutionary Biology at the Department of Biology, Lund University. “As a result, repeated evolution is more likely to occur when species share a developmental biology that makes some characteristics appear readily, while others are rare or even impossible.”

One source of these developmental biases can be found in how individuals respond to different environments, a hypothesis known as plasticity-led evolution. The researchers tested how the anoles’ bones