Nature Geography on Instagram: "Giant Siberian tigers can see any living creature as prey. They are known as the most ferocious and powerful cats. They also see humans as prey and will hunt them if they get the chance. In this video, they are trying to hunt a woman who is adjusting the trunk of her car during a picnic. The woman notices the tiger early and escapes by getting into the trunk. #tiger #sibirian #wildcats #weographic #naturegeography"

Kunal Sood, MD on Instagram: "Superfetation is the extremely rare situation where a second pregnancy begins during an ongoing one. Normally, pregnancy blocks this through three layers of protection: ovulation stops, cervical mucus thickens into a plug that prevents sperm from entering, and the uterine lining becomes unreceptive to a new embryo. For another conception to occur, all three of these safeguards would need to be bypassed. Documented human cases are very few, and most involve assisted