It is widely believed that Earth's atmosphere has been rich in oxygen for about 2.5 billion years due to a relatively rapid increase in microorganisms capable of performing photosynthesis. Researchers provide a mechanism to explain precursor oxygenation events, or 'whiffs,' which may have opened the door for this to occur....
Discovery: The great whale pee funnel moves vital nutrients
Scientists have discovered that whales move nutrients thousands of miles -- in their urine -- from as far as Alaska to Hawaii. These tons of nitrogen support the health of tropical ecosystems and fish, where nitrogen can be limited. They call this movement of nutrients a 'conveyor belt' or 'the...
A longer, sleeker super predator: Megalodon’s true form
The megalodon has long been imagined as an enormous great white shark, but new research suggests that perception is all wrong. The study finds the prehistoric hunter had a much longer body -- closer in shape to a lemon shark or even a large whale.
Bacterial ‘jumping genes’ can target and control chromosome ends
Transposons, or 'jumping genes' -- DNA segments that can move from one part of the genome to another -- are key to bacterial evolution and the development of antibiotic resistance. Researchers have discovered a new mechanism these genes use to survive and propagate in bacteria with linear DNA, with applications...
The unforseen effects of melting glaciers on Arctic coastal ecosystems
Researchers found that climate change induced glacial melt increases the heavy metal content and changes the microbiome of habitat-forming brown algae in Arctic fjords. As algae are at the basis of the food web, this will likely have cascading ecological and economic consequences.
Stretching spider silk makes it stronger
When they weave their webs, spiders pull their silk threads. New simulations show stretching during spinning causes the protein chains within the fibers to align and the number of hydrogen bonds between those chains to increase. Both factors increase the silk fibers' overall strength and toughness. Insights could be applied...
World’s oldest impact crater found, rewriting Earth’s ancient history
Researchers have discovered the world's oldest known meteorite impact crater, which could significantly redefine our understanding of the origins of life and how our planet was shaped. The team found evidence of a major meteorite impact 3.5 billion years ago.
Study raises the possibility of a country without butterflies
A sweeping study for the first time tallies butterfly data from more than 76,000 surveys across the continental United States. The results: Butterflies -- all of them -- are disappearing.
Scientists identify genes that make humans and Labradors more likely to become obese
Researchers have discovered genes linked to obesity in both Labradors and humans. They say the effects can be over-ridden with a strict diet and exercise regime.
Damaged but not defeated: Bacteria use nano-spearguns to retaliate against attacks
Some bacteria deploy tiny spearguns to retaliate against rival attacks. Researchers mimicked attacks by poking bacteria with an ultra-sharp tip. Using this approach, they have uncovered that bacteria assemble their nanoweapons in response to cell envelope damage and rapidly strike back with high precision.