Tough little frogs

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If a magical being pops into existence in front of you and demands that you choose a non-human animal into which you will be reincarnated, one of the first things you should consider is: how many babies does the species have, and how big are they? If you want a good shot at surviving past infancy in your second life, you will want to select a species that has just a few, big babies. Elephants are a good option, with their single giant offspring; ditto whales. Large sharks are a solid possibility, often birthing just two large babies at a time (but you’ll want to be careful that you don’t pick a species—such as the sand tiger shark—in which many embryos are formed in the uterus, and then all but two are eaten by their siblings before birth).

You will most certainly not want to choose to be a species whose offspring look like this:

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Cope’s gray treefrog pair with eggs

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Frog season

Frog season is upon us, and for us in the Frog Lab, regular sleeping hours are a luxury of the past. In the day we hide from the sun in basements and prepare our equipment.

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Painting frog models to perfectly match real frogs.

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Calibrating a speaker so that it ouputs the sound of a frog call at exactly 85.0 dB.

In the night, we don our chest waders, take up our headlamps, hang bags of tupperware from our wader straps, and walk into the ponds to seek our prey.

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The space-for-time substitution

Recently I flew from a particularly dire version of Minnesota winter—periodic rain making no dent in the graying heaps of snow, while rendering the smooth ice-covered sidewalks puddle-pocked and slick, so that it was not unusual to find oneself sliding inexorably down an icy slope into four inches of slushy water—into the blush of spring.

This new season was in California, where I was visiting my fiancé for the weekend. (Long-distance relationships are a staple of academia; my Minnesota labmates have significant others in Seattle and India.) Three hours on a plane headed west and I seemed to have jumped forward two months. Puffed-up robins in the snow…

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…were replaced with marsh wrens singing furious declarations of their virility.

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Other lives

It’s traditional to be thankful around this time of year in the United States, but that isn’t easy this year. Science and the environment are under serious attack, and it’s not clear that the situation will improve anytime soon. We are losing time we won’t get back: students who might have been our next scientific leaders won’t be able to afford education and will turn their careers elsewhere; species and habitats will be irretrievably lost.

It’s too easy to get buried in these discouragements, exhausted and dispirited, and turn away rather than watch more damage done. But we can’t let the things we love become things we don’t want to think about. The things we love are in peril: if we are to save them, we need to think about the love as well as the peril.

Let’s be thankful for the things we might lose. Let’s remember why we treasure them.

I am thankful for all the other lives in this world: all the alien minds, the perspectives built of senses I barely have (smell) or lack entirely (echolocation; detection of magnetic fields), the goals both remote (time to fly from Alaska to New Zealand!) and familiar (must protect my family!), the pleasures that are at once recognizable and strange (the contentment of a mother oppossum with all her babies in her pouch; the joy of a dust-bathing sparrow). I am thankful for how these other lives expand my mind and also for how they have nothing to do with me. I am thankful for the opportunity to glimpse some of them.

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One of those other lives: a one-legged (but healthy) Black Phoebe.

Very hungry caterpillars

It’s almost a pity that we introduce children to caterpillars so young. The magic of the transformation of a squishy, unimpressive tube into a living, fluttering creature apparently made of stained glass gets muddled up with the rest of the magic of childhood and is too easy to forget when we grow up. Everyone knows about caterpillars turning into butterflies, but almost no one really thinks about it.

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Photo by Andrea Westmoreland, reproduced through a Creative Common license from Flickr.

Even before they turning into butterflies (or moths), caterpillars are impressive. They hatch tiny, into a bird-eat-caterpillar world, and their one crucial job is to grow big in time to metamorphose. This isn’t a particularly complex task—there’s a reason caterpillars are basically just digestive systems on legs—but it isn’t necessarily easy, either. They need to find the right food and eat it quickly without being eaten themselves.

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Learn about speciation from that one weird duck at the park

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Every park has at least one weird duck. It’s the wrong colors—all white, or patchy white; its bill bright storybook orange or its face weirdly red and lumpy. Next to the other ducks it looks oversized and bulky, like a linebacker in a crowd of quarterbacks.

How new species form, and what determines whether they last, is one of the major topics in evolutionary biology; and much of this topic is embodied by that one weird duck.

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Bathtime, carefully

For birds, cleanliness is not optional. They rely on their feathers for flight and insulation, and only replace those feathers once or twice each year. In between molts, they need to keep their feathers as whole as possible.

Feathers, like our hair, are made of protein; and like all organic things, they degrade over time. Sunlight hastens this degradation, but certain aspects of the feathers themselves can slow it: dark feathers colored with melanin last longer in sunlight, for example. Of more concern, though, are the many creepy-crawly things that like to eat protein, and will happily hang out in a bird’s feathers, munching and laying eggs.

To combat these parasites, birds coat their feathers in protective oil from the preen gland located at the base of their tail, and they bathe.

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But they have to be careful. Small wild birds are lunch for everything from feral cats to Cooper’s Hawks, and no bird wants one of these sneaking up on it while it is obliviously scrubbing behind its ears. So they bathe in bursts, a plunge into the water followed by a quick look around.

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Did anybody see that?

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Saving individuals

Planet Earth II, the new BBC documentary narrated by Supreme Voice of Nature Sir David Attenborough, devotes one of its six episodes to animals living in cities. It’s unsurprisingly great. (Even if the ultimate masters of urban living, pigeons, who you might expect to be celebrated in this context, instead spend the episode getting unceremoniously eaten.) The “Cities” episode has to walk a delicate line, heralding animals’ ability to adapt to human landscapes without failing to acknowledge that humans overwhelmingly destroy habitat rather than creating it. It mostly leans to the optimistic side of the line; one segment makes New York City seem like a wildlife paradise.

The darker side of cities is represented by a segment on hatchling sea turtles. The turtles use the shine of moonlight on water to guide them from their nest in the sand into the ocean. Unfortunately, we humans love to shine lights even brighter than the moon, and more than half of the tiny turtles are drawn away from the ocean by the city’s lights.

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A hatchling Hawksbill sea turtle in Planet Earth II.

As Attenborough narrates, footage rolls of the baby sea turtles gamely clambering across sidewalks and onto busy streets, heading for the ocean that isn’t there. The bodies of roadkilled turtles are visible in the background. One turtle makes it across the street, then tumbles halfway into a storm grate and gets stuck, lost to view save for one forlornly-waving flipper.

As soon as the episode ended, I began typing into Google: “planet earth 2 did”—at which point Google helpfully autocompleted the rest of the sentence: “planet earth 2 did they help the turtles“. Everyone else who had seen the episode wanted to know, too.

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Scarred

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Like elephants or dinosaurs, male Northern elephant seals on land are massive past the point of useful reference. A 5000-lb animal falls off our everyday mental scale; it’s just enormous.

Yet, lounging around on the sand at this time of year—their mating season—these beasts look like they need some band-aids and Neosporin. Their thick, strong hide is marred with new gashes laid over old scars. Titans they may be, but even titans can fall when they square off against other titans.

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Two males facing off. The male on the left has blood on his nose.

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Why do birds flock in winter?

If you live in a temperate climate and pay attention to your local birds, you have probably noticed that their preferences for companionship change with the seasons. In spring, pairs stick close by each other and three’s a crowd—any third-wheel interloper is likely to be chased off in a flurry of angry wingbeats. But in fall and winter, the birds suddenly become community minded, travelling around in flocks of dozens of their fellows. In Chicago in the winter you can find trees liberally decorated with the round orange forms of fluffed-up American Robins, bearing more than a passing resemblance to Christmas tree ornaments. Even in the Bay Area, not generally known for its seasonal variation, huge flocks of quietly chirruping Dark-eyed Juncos make it clear that (mild, occasionally rainy) winter has arrived.

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Not pictured: about fifteen of this robin’s winter friends.

Why flock in winter? Or, why flock only in winter?

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