Hot Cones Cue Hungry Insects

Pine cones stay warmer than the needles around them. And hungry insects have heat sensors that spot the cones. Karen Hopkin reports

Illustration of a Bohr atom model spinning around the words Science Quickly with various science and medicine related icons around the text

Join Our Community of Science Lovers!

[The following is an exact transcript of this podcast.]

Animals rely on all sorts of cues to find their next meal. Monkeys and birds are attracted to the colors of ripe fruits and berries. And snakes find their prey by sensing heat. Now a team of Canadian scientists finds that some insects can do the same thing, sensing the infrared radiation emitted by, of all things, pine cones.

These seed-eating bugs are not the first known to home in on heat when they’re looking for food. Some blood-sucking bugs can sense the temperature of their warm-blooded hosts. But this study, published on October 22nd in the Royal Society journal Biological Sciences, is the first to find that insects can use infrared to find their favorite plants.

Pine cones, it turns out, run about 15 degrees warmer than the pine needles that surround them. In fact, the cones radiate so strongly in the infrared that they show up like candles on a Christmas tree. The bugs, which nosh on conifer seeds, can locate the toasty, seed-bearing cones thanks to special infrared receptors on their abdomens. When the scientists covered up those receptors, the insects couldn’t see the forest or the trees. And the male insects probably won’t even stop to ask for directions.

—Karen Hopkin 


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


60-Second Science is a daily podcast. Subscribe to this Podcast:

RSS | iTunes 

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe