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Yellow saddle goatfish (via wikimedia commons)

Lions, orcas, dolphins, hyenas, some hawks and several other species collaborate when they hunt, with each individual in the group performing different but complementary actions with the singular goal of bringing down prey. Now we can add a species of fish to the list of collaborative hunters–the yellow saddle goatfish (Parupeneus cyclostomus), which lives in the shallow waters of the Red Sea.

A group of researchers (who report their findings in Ethology) traveled to Egypt and spent a lot of time snorkeling, watching the goatfish, recording their behavior and taking photographs of the fish. Yellow saddle goatfish are easy to recognize underwater due to their size, color and pattern of black spots on their body and fins. Individual fish can be distinguished in photos due to differences in the shape of the blue lines around their eyes.

The goatfish often congregate in groups. And when one fish starts accelerating towards a prey fish, other members of the group join in the hunt. These “blockers” spread out over the reef to cut off the prey fish’s escape routes, giving their buddy, the “chaser,” a better chance at making a successful catch.

Other species of goatfish eat only invertebrates, while the yellow saddle variety chases other fish. The researchers suggest that the collaborative hunting behavior is essential for the yellow saddle goatfish to successfully hunt other fish on the reef and that the behavior may have evolved to allow them to exploit that source of food.

An elephant seal in bull kelp, in the Southern Ocean (credit: Christopher J. Brown)

It’s gonna get messy, particularly in the oceans. That seems to be the message in a recent Science study that analyzed the pace of climate change.

A marine sea slug (credit: Hugh Brown, Scottish Association for Marine Science)

Using 50 years of observations, “we examined the velocity of climate change (the geographic shifts of temperature bands over time) and the shift in seasonal temperatures for both land and sea,” said John Pandolfi of the University of Queensland. “We found both measures were higher for the ocean at certain latitudes than on land, despite the fact that the oceans tend to warm more slowly than air over the land.”

The changes won’t be uniform, the scientists say. And some marine organisms will have to migrate hundreds of miles to new waters to find the right temperature, seasonal conditions and food. Those that don’t move fast enough could easily become extinct.

And it isn’t as simple as moving north or south toward the poles. Like most landscapes, oceans aren’t uniform. There are land masses and deep ocean trenches and strong currents that can prevent creatures from moving from one place to another. Then there’s the question of what might take the place of the organisms that currently live in the warmest parts of the oceans. “No communities of organisms from even warmer regions currently exist to replace those moving out,” Pandolfi said.

An Adelie penguin in a blizzard (credit: Christopher J. Brown)

In an accompanying Perspective essay, biologist Ralf Ohlemüller of Durham University notes that “climate affects both evolutionary processes, such as how fast species diversify, and ecological processes, such as range shifts and species interactions.” And while that complexity of interactions will make predicting the coming changes difficult, Ohlemüller reminds us that studies like this one, which are not as detailed as we might like, are important nonetheless as they help us to “broaden our understanding of how environments change in space and time and how this in turn affects patterns of disappearing, persisting, and novel climates, species, and ecosystems.” And with that knowledge, perhaps we can be better prepared for the changes ahead.

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"Somewhere along the way, I came to the startling realization that all those equations actually mean something." (courtesy of flickr user cemre)

When I think back on how my love of science grew, I think fondly of all the science teachers who conveyed their enthusiasm for the subject to me and my fellow students. And when I went through recent reader contributions to this series (send your own to WhyILikeScience@gmail.com), I was pleased to hear from two individuals who work with students every day.

Elizabeth Fife teaches physics to juniors and seniors at Mesa High School in Mesa, Arizona:

When I was in high school I viewed science as a puzzle to be solved; my teacher would present me with a handful of variables and a paper full of equations, and I was expected to find some missing quantity. I loved rearranging the numbers and chugging through the equations, and I felt a smug sense of satisfaction once I finally figured out the path to the correct answer. But I never really understood the concepts, the actual science, behind what I was doing; it was all algebraic manipulation to me. And though I eventually decided to pursue science in college, it was not because of any high minded ideals—I liked the idea of feeling smart and making a lot of money.

Somewhere along the way, however, I came to the startling realization that all those equations actually mean something. I began to see connections and explanations, and I finally saw the elegant beauty of a world explained by science and saw that science isn’t about numbers and math—it’s about explanations and patterns and relationships. It’s about unlocking the world around us and laying it out to be admired.

This was such a powerful realization that I changed my course of study. I wanted everyone to see what I had finally come to see, that there is a beautiful elegance to the physical laws that construct and connect our world. More than just an appreciation, there is a certain joy in really understanding how the world operates and a raw excitement in the act of gaining that understanding, in making an opaque world just that much clearer.

Years later, I now find myself at the front of that exact same classroom where I sat so long ago as a know-it-all high school student. I shake my head at the ghost of my younger self who thought science was nothing more than an interesting number puzzle and a means to a lot of cash. I grin with shared excitement whenever one of my students’ eyes light up and they say, “OH. So THAT’S why…” because that is what science is and what makes it so enjoyable. It is in the realizations and connections we make, it is that shiver of excitement that accompanies those “ah-ha” moments of discovery, and it is in finding the order in an oftentimes nonsensical world.

Katherine Krein, of Sterling, Virginia, works in the special education department of a local middle school. This year she is assisting students in eighth-grade physical science:

Science enables us to stretch our senses beyond our human limitations. We cannot see the whole spectrum of light, we cannot hear all sound frequencies and we cannot see all matter. Unaided, we can only perceive what is within our range, our reach and our human scale. We cannot sense what is inaccessible to us. Science expands our access.

Science has empowered us to detect and sense the world around us. The nature of science, with its strong foundation of methods, has allowed scientists to develop tools that help us to identify the electromagnetic spectrum, which includes visible light; tools that assist us in measuring and recording all wavelengths and frequencies, including all the sounds that our ears can detect; tools to search for and find ever increasingly small particles of matter; and tools to see things that are farther and farther away from us. Through the study of science, scientists can detect the DNA in a follicle of hair or a speck of saliva, see viruses in blood, and find tumors within a body. The list goes on—the benefits to mankind are manifold.

On a more personal scale, science has given us hearing aids which help my father hear. Science has given me eye glasses that correct my near-sightedness. Science has given us medicine that helps many of us live healthier lives. Science is helping a co-worker battle breast cancer.

To say that I like science is an understatement that does not adequately express my gratitude for everything that it has given humanity, my friends and family, and me.

Nursery web spiders (Credit: Maria J Albo)

In order to mate, males of many invertebrate species must present a nuptial gift to the female before she will acquiesce and let their relationship move to the next step. Male nursery web spiders (Pisaura mirabilis) usually present an edible insect wrapped up in spider silk. But some guys are sneaky. They wrap up a useless gift, such as an inedible plant seed or the empty exoskeleton left after he’s eaten a fly. (And if his chosen female tries to steal his gift without mating with him, the spider can play dead, letting him stay near her for longer and continue the mating.)

But there’s a downside to a male’s sly behavior, scientists found in a new study published in BMC Evolutionary Biology. Offering a gift of any kind, either real or fake, was more likely to lead to a spider getting some nooky, but males that presented a yummy treat were able to spend more time mating, and more time transferring sperm, than the guys who tried handing over a counterfeit contribution. “The females are wise to the deception and terminate mating early for worthless gifts,” says the study’s lead author, Maria Albo of Denmark’s Aarhus University.

Females may detect the liars, but it turns out that lying doesn’t have any bad consequences when it comes to fathering baby spiders. “The final results show that the number of eggs hatching was lower if the female had not received a gift,” Albo says, “but there was little difference between females who had received an edible or inedible gift.” And because both strategies–giving a real gift and passing a fake one–result in a successful transfer of a male’s genes to the next generation, evolution apparently hasn’t favored one over the other.

A nearly dry horseshoe lake at Brazos Bend State Park, Texas (photo by Sarah Zielinski)

“What is this, rain? I was promised a drought,” I joked to a friend as we drove through ten seconds of drizzle this weekend in Houston. I needn’t have worried–the rest of the day was sunny and warm. It was a pleasant diversion from the cooler temperatures of a mid-Atlantic fall, but in Texas, warm and dry has become a real worry. The entire state is in the midst of an exceptionally bad drought, as you’ve probably read in the news. But what does that look like on the ground?

In Houston itself, there isn’t too much evidence of the drought. Sure, the lawns and plants may look a little brown in places, and there’s the occasional sign notifying people of watering restrictions. But if your vision of drought is wildfires or the Sahara Desert, you’re bound to be disappointed.

An alligator suns itself on the edge of Elm Lake (photo by Sarah Zielinski)

Even outside the city things don’t seem so bad at first glance. It’s a bit dusty, and the cows are munching on bits of grass in rather brown fields. When we started walking around Brazos Bend State Park, however, the drought quickly made itself known. One horseshoe lake had water and made a nice home for several alligators, but the other was full of dead vegetation and had only one tiny little patch of water, barely suitable for small birds looking for a drink. The park’s largest body of water, Elm Lake, which appears as a large patch of blue on a map of hiking trails, had shrunk around the edges and the shallow water was often covered in a nasty green algae. On the bright side, the alligators clustered near the water along the edge of the lake, which made them easy for us to find.

The effects of a drought come in ways we often don’t expect. Migrating birds will be fewer in Texas this year, and they’ll have fewer places to stop. That will give hunters fewer opportunities to pursue their hobby. Migrating monarch butterflies will find it more difficult to cross the state on their way to Mexico; they’ve already had a bad year, dealing with the drought in the spring and a cooler summer around the Great Lakes. Cattle ranchers have sold off parts of their herds; with grass and water scarce, and importing hay from other states expensive, they can’t afford to keep so many animals. The price of beef, and other foodstuffs, will likely rise. Even drought-tolerant plants are not immune from a drought this bad. Power generation, heavily dependent on water, could take a hit. Communities are opposing new projects that would use up the little water available.

The last 12 months have been the driest since record-keeping began in 1895. And a few inches of rain will do little to alleviate the precipitation backlog (26 inches in Central Texas). But Texas, even the United States, isn’t alone in this problem. Climate change will likely bring more droughts around the world. As I reported last year in Smithsonian:

Other regions—the Mediterranean, southern Africa, parts of South America and Asia—also face fresh-water shortages, perhaps outright crises. In the Andes Mountains of South America, glaciers are melting so quickly that millions of people in Peru, Bolivia and Ecuador are expected to lose a major source of fresh water by 2020. In southwestern Australia, which is in the midst of its worst drought in 750 years, fresh water is so scarce the city of Perth is building plants to remove the salt from seawater. More than one billion people around the world now live in water-stressed regions, according to the World Health Organization, a number that is expected to double by 2050, when an estimated nine billion people will inhabit the planet.

“There’s not enough fresh water to handle nine billion people at current consumption levels,” says Patricia Mulroy, a board member of the Colorado-based Water Research Foundation, which promotes the development of safe, affordable drinking water worldwide. People need a “fundamental, cultural attitude change about water supply in the Southwest,” she adds. “It’s not abundant, it’s not reliable, it’s not going to always be there.”

Water, either too much or too little, is one of the biggest problems we can blame on climate change. At least in places like the United States and Australia, there is enough money for a drought to be no more than an inconvenience. In other parts of the world, however, water problems are going to end in human deaths.