Parasite Affects Instinctive Fear

A common single-cell pathogen (Toxoplasma gondii) removes the instinctive fear of predators (cats) in rodents, possibly permanently modifying a specific brain function as an evolutionary adaptation for the parasite, which can only reproduce sexually within the cat gut.

Weak Force Directly Measured

Researchers with the Q-weak experiment at the Jefferson National Accelerator Facility have made the first direct measurement of the value of the weak force, one of the four fundamental forces described in the Standard Model, for the proton, the neutron, and the up and down quarks.

Functioning Gears in Nature

Scientists have found the first example of a naturally occurring gear mechanism in the hind leg joint structure of the plant hopper (Issus coleoptratus) featuring interlocking cog teeth that ensure a coordinated thrust when the insect jumps with a mechanical synchronization beyond what is capable with the nervous system.

Evolution Through Exaptation

A new quantitative study gives further support to the new biological concept of exaptation, an evolutionary phenomenon introduced in 1982 by Stephen Jay Gould and Elisabeth Vrba as a counterpart to adaptation by which existing traits are co-opted for new and advantageous uses unrelated to their biological origin.

Seismic Waves Reveal Hotspots

Scientists have taken advantage of a previously unknown type of slow-moving seismic waves to map channels of heat flow and "hotspots" of volcanic surfacing in Earth's mantle using new models similar to computerized tomography (CT) scans of the human body.

Convergent Evolution in Genes

Geneticists studying 2326 genes in 22 mammal species have found widespread "convergence signatures" in over 200 regions for biological traits, showing that convergent evolution of similar anatomical and functional features such as sight and echolocation across unrelated species is more widespread at the molecular level than previously thought.

New Timeline for Ancient Egypt

Using radiocarbon dating of excavated hair, bones and plant materials along with established archaeological evidence and computer models, scientists have pinpointed a revised timeline for the rise of Egypt's first state dynasty with King Aha about 3100 B.C.

Younger Dryas Asteroid Impact

Scientists have found mounting evidence of unique mineral signatures in North America and Greenland soil samples indicating an asteroid impact near modern-day Quebec about 12,900 years ago, corresponding to archaeological global climate cooling and the most recent ice age known as the Younger Dryas.