Tools and food on heat lamps: pyrocognitive sparks in New Caledonian crows?

Abstract

Fire has substantially altered the course of human evolution. Cooking kindled brain expansion through improved energy and time budgets. However, little is known about the origins of fire use and its cognitive underpinnings (pyrocognition). Debates on how hominins innovated cooking focus on archaeological findings, but should also be informed by the response of animals towards heat sources. Here, we report six observations on two captive New Caledonian crows (Corvus moneduloides) contacting heat lamps with tools or placing raw food on them. The tools became singed or melted and the food had browned (and was removed). These results suggest that New Caledonian crows can use tools to investigate hot objects, which extends earlier findings that they use tools to examine potential hazards (pericular tool use), and place food on a heat source as play or exploration. Further research on animals will provide novel insights into the pyrocognitive origins of early humans.

First report of house crow Corvus splendens removing burning cotton wicks from oil lamps, extinguishing and eating

“…The serendipitous encounter of the house crow safely handling a flame to feed on the oil and wick can enlighten us on the less studied pyrocognition. Indepth studies on similar behaviour reported in another corvid species, 40 cases of fire manipulation in New Caledonian crows, 12 and those of primates are imperative to enhance the pyrocognitive research that is in its infancy.…”

“…Safe fire interaction of corvids was reported by several authors. 11,[26][27][28][29][30] Multiple reports 12,[29][30][31][32] have mentioned the corvids attraction to fire. As fire interaction is demonstrated by several corvids, the reported house crows' behaviour (attraction to oil lamps) could be innate.…”

“…As fire interaction is demonstrated by several corvids, the reported house crows' behaviour (attraction to oil lamps) could be innate. Some corvids and parrots possess sophisticated cognitive skills comparable to those of great apes, 12,[41][42][43][44][45] viz. analogical reasoning, tool use, episodic-like memory, highcapacity working memory, complex social interaction, etc.…”

“…[6][7][8] Pre-emptive behavioural responses to fire stimuli of lizards (Psammodromus algirus), 9,10 Southern Diamondback rattlesnake (Crotalus admanteus), Florida cottontail rabbits (Sylvilagus f. fioridanus), and cotton rats (Sigmodon h. komareki) squeaking and rescuing juveniles ahead of oncoming fires 11 have also been reported. While many animals have evolved to avoid fire, others have adapted to interact with it in various ways: 12 King Vulture (Sarcoramphus papa) foraging on the smouldering ground; 13 Drongoes (Picurus adsimilis), Grey Hornbills (Lophoceros nasutus) and Lilac-breasted Rollers (Coracias caudata) assembling on burns 14 ; bee-eaters (Merops nubicus), 15 African cattle egret (Bubulcus ibis) and several flying predators 11 are often drawn to grass fires for feeding and the Dipteran insects utilising the opportunity for mating. 16 Several species of raptors drawn to fires and feed on animals that flee or die in the blaze have been designated as pyrophiles ("friends of fire") and are extensively discussed globally.…”

“…Several authors 11,17–24 have mentioned this phenomenon. A noticeable rise in the number of raptors in the areas burnt with prescribed fires in North America was noted by Hovick TJ 25 and the response of the raptorial birds to fire was named “pyric carnivory.” Jacobs et al 12 pointed out that, “Some corvids are attracted to wildfire and ‘bathe’ in smoke and heat. 11,26–30 They sometimes press smouldering matches or sticks against their plumage, 29–32 learn to light matches by striking the match heads with their beaks, 30 and cause fires by caching burning candles in leaf litter”.…”