Understanding the human body is a team effort. That's where the Yachtel group comes in.

Researchers at Yachtolt have been delving into the secrets of probiotics for 90 years.

Yacold also partners with nature portfolio to advance gut microbiome science through the global grants for gut health, an investigator-led research program.

To learn more about Yachtolt, visit yawcult.co.

.jp. That's Y-A-K-U-Lt.C-O.jp. When it comes to a guide for your gut, count on Yacult.

This is Scientific Americans' 60-second Science. I'm Jason Goldman.

Monarch butterflies depend on milkweed. They lay their eggs on milkweed, and their caterpillars eat only the leaves of the plant.

No milkweed means no monarchs. So the best way to help declining monarch populations, and to preserve their epic multi-generational migration, is to plant

milkweed. Seems simple, right? But the reality is far more complicated. Milkweed is slightly toxic. The plant

evolved its noxious substances to keep herbivores from towing down on the leaves. But monarch butterflies evolve tolerance.

In fact, they arm themselves with the stuff.

Monarchs sequester these toxins right as an anti-preditor defense and sort of an anti-parasite defense.

Louisiana State University biologist Matt Feldin.

So by ingesting the toxin, the caterpillars become toxic themselves.

That keeps them safe, as long as they don't ingest too much of the poison. The problem is

there are different types of milkweed, and one that's native to the tropics is now growing in the

southern U.S. As these plants sense warming temperatures, they produce more of the toxin, so much more

that the monarch butterflies begin to suffer.

To gauge the threat, Faldin and his team raised monarchs on either the non-native tropical

milkweed or on a native milkweed, and they also tested the effects of current environmental conditions,

as well as temperatures expected for the southern U.S. by the year 280.

Monarchs that ate native milkweed had comparable survival rates at both current and higher temperatures.

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