Hawaiian Bobtail Squid

THE LIGHT ORGAN OF THE HAWAIIAN BOBTAIL SQUID

           A NOCTURNAL hunter, the Hawaiian bobtail squid creates its own light—not to be seen, but to be unseen—to blend in with the ambient moonlight and starlight. The animal’s secret is its partnership with light-emitting bacteria. That partnership may also hold secrets that could benefit us, but in a seemingly unrelated way. It may benefit our health.

      Consider: The Hawaiian bobtail squid lives in the clear coastal waters of the Hawaiian Islands. Light from the moon and the stars would normally make the silhouette of the creature stand out to predators below. The bobtail squid, however, emits a glow from its underside that mimics ambient night light in both intensity and wavelength. The result is stealth—no silhouette, no shadow. The squid’s “hightech” apparatus is its light organ, which houses bioluminescent bacteria that produce just the right glow to camouflage their host. The bacteria may also help to regulate the squid’s sleep-wake pattern. This interests researchers because the bobtail squid may not be the only creature where there is a link between bacteria and circadian cycles, or daily rhythms in activity. In mammals, for example, bacteria that play a role in digestion may also be associated with circadian rhythms. Disturbances of these rhythms have been linked to depression, diabetes, obesity, and sleep disorders. Hence, the study of the squid’s bacteria-host system may furnish insights into human health. What do you think? Did the light organ of the Hawaiian bobtail squid come about by evolution? Or was it designed?

Wings of Soaring Birds

The Upturned Wing Tip of Soaring Birds

       AJET plane in flight creates rapidly spiraling swirls of air at the tips of its wings. These vortices cause drag, increasing fuel consumption. They also buffet planes that may be following closely. Thus, flights departing from the same runway must be sufficiently spaced to allow time for the vortices to dissipate.  Airplane engineers have discovered a way to reduce these problems. Their solution? Winglets, inspired by the upturned wing-tip feathers of soaring birds, such as buzzards, eagles, and storks.

Consider:   During flight, the feathers on the wing tips of those large birds bend upward until they are almost vertical. This configuration balances maximum lift with minimum wing length. It also improves performance. Engineers have designed airplane wings with a similar shape. Using innovative wind-tunnel testing, they found that if the modified wings were precisely curved at the tip and properly aligned with the airflow, they improved aircraft performance—nowadays by up to 10 percent or more. The reason? Winglets minimize drag by reducing the size of the vortices. Moreover, winglets also create a form of thrust that “counteracts some of the normal drag of the airplane,” says the Encyclopedia of Flight. Winglets thus enable airplanes to fly farther, carry a greater load, have shorter wings—which also facilitates parking—and save fuel. In 2010, for example, airlines “saved 2 billion gallons [7,600 million L] of jet fuel worldwide” and contributed to large reductions in aircraft emissions, says a NASA news release. What do you think? Did the upturned wing tip of soaring birds come about by evolution? Or was it designed?

Crocodile's Jaw

 CROCODILE'S JAW

     THE crocodile has the most powerful bite ever easured for animals that are now living. For example, the saltwater crocodile, found near Australia, can bite nearly three times as hard as a lion or a tiger. Yet, the crocodile’s jaw is also incredibly sensitive to touch—even more sensitive than the human fingertip. How can that be, considering the crocodile’s armored skin? The crocodile’s jaw is covered with thousands of sense organs. After studying them, researcher Duncan Leitch noted: “Each of the nerve endings comes out of a hole in the skull.” This arrangement protects the nerve fibers in the jaw while providing sensitivity that in some spots is greater than instruments could measure.  As a result, the crocodile can distinguish between food and debris in its mouth.  That is also how a mother crocodile can carry her hatchlings in her mouth without accidentally crushing them. The crocodile’s jaw is a surprising combination of power and sensitivity. What do you think? Did the crocodile’s jaw come about by evolution? Or was it designed?