Great news for the nearly-extinct monarch butterflies, which will pass through the area as they migrate back to Mexico. Also, to find out how blood affects aging, scientists can surgically connect two animals and let blood circulate between them.After California’s Park Fire, A Second Bloom of MilkweedDon Hankins examines a bright yellow-green patch in the meadow. The land all around is charred by fire. But here, there’s a sort of miracle at work. Native milkweed has sprung up and bloomed for the second time this year. This is not something these plants, Asclepias eriocarpa, also known as Indian milkweed, are known to do.They bloomed in late spring and early summer and had already done so this year when the Park Fire roared through. But the fire seemed to happen at just the right time to coax a second flowering, one that is likely to line up with the return migration of the monarch butterflies south to overwinter in Mexico. Monarchs rely on these flowers to complete their life cycle. For researcher Don Hankins, this is a surprise delight.“We may be coming back into some knowledge here that hasn’t been practiced in a long time,” said Don Hankins, a professor at Chico State, who teaches classes in geography with a focus on fire. He is also a California Plains Miwok traditional cultural practitioner.Read the rest at sciencefriday.com.Inside The ‘Creepy’ Procedure That Taps Into Young BloodWhile fictional vampires suck the blood of the young to live forever, some researchers have found that certain elements in young blood actually can improve the health of the old. This is possible through a spooky procedure called parabiosis, in which the circulatory systems of two animals are joined, letting the blood flow from one into the other.By connecting old mice and young mice through parabiosis, researchers have observed how different molecules in the blood impact symptoms of aging. While some outcomes have excited experts, enthusiastic biohackers attempting to defy their own aging might have jumped the gun. There’s a long way to go before we understand how elements of young blood might be harnessed to treat aging humans.Emma Gometz, SciFri’s digital producer of engagement, talks to Dr. Tony Wyss-Coray, a neurology professor at Stanford University who has used parabiosis (which he once described as “creepy”) to help reveal how components of our blood affect our cognition as we age. They discuss parabiosis, vampires, and how far the field has to go before humans can benefit.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.