Toxins and venoms: nature's poisons

BBC Wildlife|July 2023

WITH EVOLUTIONARY BIOLOGIST JV CHAMARY

- JV CHAMARY

WHEN ASKED TO NAME substances that cause sickness or death, many people would mention. poisons that are harmful to humans - chemical elements such as arsenic, plants such as hemlock, or death cap mushrooms. In fact, nearly every major group of organisms makes natural poisons, which come in two flavours: toxin and venom.

What's the difference between a toxin and a venom?

They're distinguished by delivery route. A toxin passively enters a recipient's body after being swallowed, inhaled or absorbed through contact. By contrast, a venom is actively delivered into a victim via a bite, spray, stab or sting. But you can't simply. say that toxins are ingested and venoms are injected. When the toxin tetrodotoxin is delivered through the bite of a blue-ringed octopus, it's then technically venom! The two poisons also differ by function.

Toxins are typically used for defence, to deter predators or competitors, venoms are used for offence, to catch prey. They have different compositions, too. A toxin is typically a single molecule and a venom is a mixture that will include toxins. Marine cone-snail venoms can contain over 100 distinct toxins to target a variety of prey.

Where do they come from?

この記事は BBC Wildlife の July 2023 版に掲載されています。

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この記事は BBC Wildlife の July 2023 版に掲載されています。

7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアムストーリー、9,000 以上の雑誌や新聞にアクセスしてください。

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