Even before the very rules of life were changed by the discovery of an arsenic-based microbe in a California lake (or were they? More next week.), this week seemed to be full of strange and interesting science involving animals. While ScienceLife works on a bunch of research that is under embargo until later this month (disclaimer: none of them involve extraterrestrial life), here are a few bullet-pointed studies that inspired awe and wonder this week.

• Optogenetics is the technique of creating mutant mice with cells that can be modulated with flashes of light, which is awesome. For example, a scientist can introduce a gene into a mouse strain that makes motor neurons sensitive to light, and when light is shined at those neurons, the mouse starts running. Now, researchers from Stanford and UT Southwestern have used optogenetics in the frontal cortex of a mouse strain, and found a way to produce anti-depressant-like effects (pdf). As covered by David Dobbs at Wired, the technique may offer a new non-invasive way of treating depression way down the line; for now, optogenetics requires a brain implant, which is less than ideal clinically.

• Telomeres, the long repeated sequences at the end of chromosomes, were a fashionable scientific buzzword before optogenetics was even a glimmer in science’s eye. With their companion enzyme telomerase, telomeres were hyped to be the genetic key to the  “fountain of youth,” the biological source of the cell damage that accompanies aging. But despite being the subject of last year’s Nobel Prize in Physiology or Medicine, the excitement about telomeres seemed to have faded out. But an exciting new study published in Nature this week may reignite that flame, as scientists at Harvard reversed the premature aging of a special mutant mouse with telomerase treatment. Wired, Ars Technica, and the Wall Street Journal discussed this “Ponce de Leon” effect, but Discover blog 80beats urges patience for those waiting on anti-aging pills.

• Scientists have long used animal models to study the neurobiology of fear in laboratory settings. But how do you realistically recreate situations that would cause a rat to be scared in the wild in the predator-free world of the animal facility? For one group of scientists, the answer was Robogator, a simulated predator designed to leap out at rats as they moved foraged for food in their lab environment (you can download video clips here). Researchers looked at how close the rat would approach Robogator before and after a lesion of the amgydala, a brain region thought to be involved in fear response. Before the lesion, the rats would only get food 10 inches or less from the entrance to their chamber, but after the lesion, they would go as far as 50 inches, sometimes even approaching and investigating the robot (video) without fear.

• Here’s a novel effect of environmental pollution upon wildlife: when ibis birds of South Florida are exposed to the most potent form of mercury, they opt for homosexual pairings over heterosexual matches.