Before getting into my science topic of the day, here is an item I received this morning from the  New York Times .  There are fewer international students coming to the U.S. Why? The decline is occurring as the Trump administration has   delayed visa processing , instituted   travel bans   or restrictions for 19 countries,   threatened to deport   international students for   pro-Palestinian speech , and   heightened the vetting   of student visa applicants . The New York Times  also reported: The civil war in Sudan has displaced 12 million people and may have killed about 400,000. It is, as Declan Walsh, our chief Africa correspondent, called it, “the world’s worst humanitarian crisis.” Experts call it a genocide. Read more about   the escapees from El Fasher . And finally a third story: Baby Shark:   In news from the world of apex predation, a pod of killer whales in the Gulf of California   hunts juvenile great wh...