THE NATURAL MOMENT 



UP FRONT 



Sec piTC edit two pa^es 



Crashing an Oscar afterparty is 

 easier than gaining entree 

 into Central America's nocturnal 

 world. Above one Panamanian is- 

 land, some seventy-three bat species 

 dominate the night sky. Yet as vet- 

 eran photographer Frans Lanting 

 discovered, seeing, hearing, and 

 tracking the bats' active nightlife 

 takes some serious legwork. 



To document the comings and 

 goings of the bulldog bat (Noctilio 

 lepoivnis), Lanting began by locating 

 a fish-fiUed lagoon. Bulldog bats, 

 a.k.a. fisherman bats, hunt for small 

 fish that break the water's surface. 

 The bats also prey on insects, but in 

 the dry season, from December to 

 April, the insect populations plum- 

 met, and the bats are more likely to 

 dip into the water for their meals. 



Bats chatter in high-frequency 

 pulses beyond the range of human 

 hearing, at a rate of more than a 

 dozen pulses a second. By inter- 

 preting the echoes of the pulses, the 

 bats can "see" in the dark. When a 

 fish jumps, for instance, it gives 

 away its position to any bulldog bat 

 on the prowl; all the bat then has to 

 do is estimate where the fish is 

 headed undenvater, and grab it. 



Bats can swoop down at more 

 than sixty miles an hour, so lighting 

 one up for a photograph takes 

 some incredibly fast reflexes. With 

 help from scientists on Panama's . 

 Barro Colorado Island, Lanting 

 found a solution. Six strobe lights 

 were set up to fire automatically 

 when a bat-size creature triggered 

 their infrared sensors. 



All of Lanting's preparation ob- 

 viously paid off, but he still credits 

 his glimpse of the bat world to a 

 bit of serendipity. — Erin Espclic 



Fly on the Wall 



The alien body part pictured on our cover is nature's answer 

 to gravity. Note the hairlike structures brisding from the 

 base of the large green hemisphere in the center. Each lit- 

 de hair exudes a spot of fluid, the better to cling to surfaces pitched 

 at impossible angles. Marvel at the two-pronged claw attached to 

 the appendage projecting in the front — not, it turns out, a weapon 

 for tearing into the flesh of prey, but a fulcrum or pivot point for 

 prying the sticky hairs off a surface and moving on. Adam Sum- 

 mers reveals all the exotic details in his "Biomechanics" column 

 this month, titled "Shoe Fly" (page 28). 



Summers, by your responses, writes two of the most intriguing 

 pages we print in Natural History every month. His beat is the 

 living world, but his take on that world is all about leverage and 

 linkage, hydraulics and aerodynamics — in short, the mechanical 

 principles that come, well, naturally, to any living thing trying to 

 make its way in nature. That includes any creature that has mas- 

 tered the ability to run, fly, breathe, pump blood, or, as in the case 

 of the highly magnified foot of the green dock leaf beetle in our 

 cover image, cling to walls and ceilings. 



• • • 



Neil deCrasse Tyson has a more figurative take on the phrase 

 "fly on the wall" in his "Universe" column, "Exoplanet 

 Earth" (page 20). In Tyson's fancy, the observant but unseen "fly" 

 is an altogether diflerent kind of alien: a civilization from another 

 star system. What could such aliens learn about our planet if they 

 turned powerful instruments on . . . us? 



If you're like me, the answers will surprise you. They probably 

 couldn't see the Great Wall of China, any more than astronauts 

 can see the structure from the Iiiteniatiotial Space Station. But if the 

 aliens were smart enough to sort the colors of our light output in- 

 to a spectrum, they would certainly detect an atmosphere far out 

 of equilibrium — a prett\' good signal that something down here is 

 strange enough to be alive. 



That brings me to the biggest question in this month's issue — 

 one of the biggest questions I can imagine: How did life arise on 

 Earth? Antonio Lazcano has pondered that question in molecular 

 detail for most of his career as a biologist, and in his article, "The 

 Origins of Life" (page 36), he presents a masterful account of the 

 state of the discipline. 



• • • 



Many readers were inspired to voice their opinions about 

 our special issue on "Darwin & Evolution" (November 

 2005) — so many, in fact, that even after we expanded our "Let- 

 ters" department this month, we still had many more thought- 

 provoking responses than we could squeeze into just one issue. 

 The first installment begins on page 1 1. 



— Peter Brown 



8 



NATURAL HISIORY February 2006 



