Irregular Webcomic! #1184

Many species of frogs secrete toxic substances of various potencies. The 150 or so species of poison dart frogs are particularly nasty.

2015-09-01 Rerun commentary: Poison dart frogs produce what is known as batrachotoxin, from the Greek βατραχος, or batrachos, meaning "frog".

Batrachotoxin is one of the most lethal alkaloid compounds known, with doses as low as 2 parts per billion of body mass being lethal in rodents. It is a neurotoxin, meaning it affects the operation of the nervous system. Specifically, it opens sodium ion channels, forcing them into a permanently open state, which upsets the electrochemical balance of the nervous system. Basically, it renders the nerves incapable of firing, so they cannot transmit messages from the brain or the unconscious autonomic nervous system controlling internal organs. The result is paralysis both of voluntary muscles, and unconsciously controlled organs. As you can imagine, this is seriously dangerous, and quickly results in death.

Not content with merely being one of the most lethal neurotoxins known, batrachotoxin also acts independently on the heart muscle directly, causing arrhythmia, fibrillation, and cardiac arrest. As you can imagine, this combined with the nervous system effects already described above is an extremely nasty combination.

There is no known effective treatment for batrachotoxin poisoning, so don't go around touching frogs at random if you're in South America. Interestingly though, one potential treatment is tetrodotoxin, the also incredibly deadly toxin found in the infamous Japanese fugu puffer fish, as well as some other creatures. This is because tetrodotoxin works in exactly the opposite way, shutting down and permanently blocking the sodium channels of the nervous system, which also results in paralysis and organ failure due to nerve signals being blocked. Presumably at some ratio of batrachotoxin to tetrodotoxin, the two competing mechanisms would (at least partially) cancel and you'd be better off than if you had just one of them in your system. Though frankly, I still wouldn't lay any bets on your chances of survival.

Further interestingly, it's not only frogs who produce this specific batrachotoxin compound. It's also produced by a few species of beetles, both in South America and New Guinea. Furthermore, there are some species of otherwise innocuous birds in New Guinea who eat these beetles without harm, and then sequester the toxin in their feathers. This makes these birds potentially dangerous to handle.

Yes, nature really is out to get you.