As November approaches, antifreeze is making its way onto shopping lists across the Northern Hemisphere, but the substance predates the existence of cars — and shopping lists, for that matter. Biological antifreezes have been enabling the existence of a variety of life forms in both hemispheres long before human beings were ever aware of their uses.

Life forms inhabiting such inhospitable locales as the frigid water below the Antarctic ice sheet and a frozen forest floor are not only bacterial and fungal organisms — some few animal species manage the feat as well. Wood frogs freeze solid every winter, only to be revived from dormancy with the spring thaw. Antarctic fish species are now known to live despite shards of ice that form in their bloodstreams. Yellow mealworms are able to lower their body fluid freezing point by up to 5.5 degrees centigrade below the melting point.

Yet how these organisms manage to survive such adverse temperature conditions remained a mystery until the discovery of natural antifreeze proteins, called AFPs, in Antarctic fish species in the late 1960s.

In winter 2013, scientists from the United States, Canada and Israel set out to discover what makes life possible for seemingly regular (that is, non-extremophile) plants and animals that persist in sub-zero (centigrade) temperatures.

Researchers from the Hebrew University of Jerusalem, in collaboration with scientists from Ohio University and professors from the University of California and Queens University in Ontario studied Tenebrio melitor  (the yellow mealworm), whose antifreeze protein is exponentially more effective than those of fish and plants, according to Science Daily.

The international team found that the presence of T. melitor AFPs in a solution is sufficient to prevent ice growth by binding to the crystals as they begin to form in a sub-zero solution. This biological technology has already been applied for human benefits: fish AFPs are currently used in ice creams to prevent undesirable ice recrystallization (more commonly known as freezer burn).

Researchers suggest that AFPs hold promise in medical fields as well — promising the potential to improve the quality of stored tissues for transplantation and of frozen sperm, ovules and embryos. It has also been suggested that AFPs may be of use to increase the survival rates of agricultural crops currently at risk from inhospitable drought and low temperature conditions in regions around the world.

A study released this year, however, has uncovered another, darker aspect of AFPs. According to a National Science Foundation report released this year, the antifreeze proteins in the blood of Antarctic fish have unfortunate and paradoxical “anti-melt” side effects.

Ice crystals, which the proteins prevent from growing in cold temperatures, are extra-resistant to melting when warm temperatures return, and this is a result of the very proteins that function as an antifreeze when the temperatures plummet.

“What we found,” reported University of Oregon doctoral student Paul Cziko, “is that the antifreeze proteins also stop the internal ice crystals from melting.”

The researchers have yet to identify harmful effects of the lingering ice in fish tissues, but suspect that they exist. University of Illinois Professor Chi-Hing Cheng, also involved with the study, suggests that the crystals could obstruct the fish’s circulation or incite inadvertent inflammatory responses.

Cziko described the findings as “just one more piece in the puzzle of how notothenioid [fish species] came to dominate the ocean around Antarctica.” The study represents just one more piece in the puzzle of AFPs, which is still taking shape.