This Plant Defends Its Sexual Organs with an Army of the Dead

A weekly roundup of the best in science journalism, doodled.

July 30, 2015

This plant creates a booby trap by coating itself with the bodies of its victims.

The serpentine columbine, which grows in wet areas along the northern California coast, has beautiful red, pointy flowers. Unfortunately, the caterpillars of the Heliothis phloxiphaga moth love to eat those buds, along with its fruits—in other words, all of the plant’s reproductive organs. The serpentine columbine, however, is wilier than meets the eye. With its sticky stems, it creates a death trap for the caterpillars (and others).

The plant sends out a chemical signal to attract insects like dragonflies and beetles, which then become entrapped by trichomes, or hooked hairs, on the stem’s surface. By coating itself with the bodies of dead and dying insects, the serpentine columbine attracts larger arthropods looking for a snack. Spiders have evolved not to stick to the adhesive surface, and while they are dining on the plant’s prisoners, they also eat those pesky caterpillars, helping the plant’s reproductive bits stay intact.

So the next time you’re strolling though a garden in NorCal and see a pretty red flower, take a closer look at the carnage...and watch your step.

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Cut your carbon pollution…or Miami gets it.

A paper that came out last week has been causing quite a stir for what it has to say about sea-level rise (and also because it was published before it was peer-reviewed). The study warns that if we keep burning fossil fuels at our current rate, we’ll face 10 feet of sea-level rise by the end of the century. The authors, who include James Hansen and 16 other prominent climate scientists, say Antarctica and Greenland will melt 10 times faster than previously predicted.

Combining that kind of sea-level rise with storms made increasingly crazy by climate change would bring severe and deadly damage to our coastal communities. The authors argue that the internationally agreed-upon goal of curbing global temperature rise at two degrees Celsius is actually too high. We need to stop viewing climate change by that “safety guardrail,” they write, because that much warming would still make many major coastal cities uninhabitable.

Back Bay Boston

Pay attention people. Take a break from reading up on how Caitlyn and Kanye are getting close and consider what’s at stake globally. It’s an uncomfortable thing to focus on, but chin up: Reversing this tide of carbon-fueled warming is not impossible. Hansen and co. say that cutting carbon emissions by 6 percent a year might be all it would take to stop the seas from crashing in as predicted. And we can start by using and investing in the carbon-neutral energy sources already available. Sounds like a pretty good deal in exchange for saving Miami and New York City and New Orleans and…

Before-and-after images by visual artist Nickolay Lamm with data developed by Climate Central

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Dolphins have to scream to be heard above our noise.

Light can’t penetrate deep ocean waters, but sound waves travel easily through the depths. This is why so many marine animals navigate their dark underwater worlds via sound. Over the last century, humans have been getting noisier and noisier under the waves, transforming a soundscape once dominated by animals Shipping sounds and naval operations emit the same low-frequency wavelengths that whales use to communicate, and companies looking for oil and gas deposits under the seafloor send explosively loud air gun blasts that radiate in all directions. 

A recent study found that dolphins basically have to shout to be heard above the ever-increasing din—and this requires more oxygen and more calories. Marla M. Holt, a biologist at the National Oceanic and Atmospheric Administration, and her colleagues trained a pair of bottlenose dolphins at the Joseph M. Long Marine Laboratory at the University of California, Santa Cruz to produce low-frequency and high-amplitude calls on demand. They monitored the animals’ oxygen intake during both types of calls and found that the louder the calls, the more O2 the dolphins needed to make them. They also found that dolphins burn two additional calories for each high-amplitude yell.

That may seem like no big deal, but imagine you’re an animal that needs to make noise to find food, but making those sounds is now burning through calories faster than you can replace them. Now say  you’re young and new to hunting, or pregnant and need calories to grow a baby—that energy hit is going to damage your health.

And that ain’t right.

Holt’s next step is to find out what we could do to minimize the racket. Because whether it’s by slowing down our ships in harbors or keeping our whale-watching boats at a respectable distance, we need to learn to keep it down.


onEarth provides reporting and analysis about environmental science, policy, and culture. All opinions expressed are those of the authors and do not necessarily reflect the policies or positions of NRDC. Learn more or follow us on Facebook and Twitter.

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