From high-speed videos, they were able to rule out direct hydrodynamic forces acting on the neck, as they could clearly see protective air cavities forming around it upon entry.
These models were sent plunging into the water at different speeds. This suggests these birds are quite conservative, diving three times slower than they feasibly could. Despite the evolutionary adaptations, diving is not entirely risk-free, even for such supremely adapted birds. Back in , nutritional ecologist Gabriel Machovsky-Capuska observed the carnage that can result from mass dives, with video footage and autopsies of New Zealand gannets revealing dozens of birds colliding underwater and sometimes impaling one another with their sharp beaks.
Hore concluded that there was interference emanating from AM radio signals and electronic equipment in operation on campus. It was only when the researchers covered the huts in aluminum sheeting and electrically grounded them to block all the EM noise in the problematic frequency range other than the earth's static magnetic field, that the birds regained their navigational ability.
Hore suggested that the EM noise is affecting the ability of cryptochrome to perform its function at a quantum level. When the radicals first form, they are entangled, so radical pairs in cryptochrome could have the unusual ability to preserve their quantum coherence for much longer than previously believed possible.
Beetle Mania. Finally, let us consider the question of how species with very small brains nonetheless are able to perform fairly complex tasks -- something that could help scientists design more effective simple machines capable of performing similar complex tasks.
Robert Noest, a graduate student in Z. Jane Wang's lab at Cornell University, reported on his work investigating how the tiger beetle manages to accurately assess distance from its prey even when both predator and prey are scuttling about. Wang's lab is known for investigating how insects fly; one intriguing question is, why they fly in certain directions.
But it's a difficult thing to study with flight movement in 3D, so they opted to study tiger beetles scuttling along a 2D plane -- a standard "chasing problem. The tiger beetle is a fascinating creature, an aggressive hunter that can run 5 MPH at top speed -- okay, maybe that doesn't sound too impressive, but think about how tiny the beetle is.
This translates into being able to cover times its body length per second, according to Cornell entomologist Cole Gilbert , who has collaborated with Wang's lab on this research. A cheetah, in contrast, covers 13 times its body length per second. It's so fast that it blurs the beetle's vision -- think of trying to photograph any fast-moving object using a camera with woefully slow shutter speed -- giving the creature a bizarre herky-jerky gait when it hunts.
He teamed up with Wang's lab to figure out the physics behind this odd behavior. Noest and his cohorts in Wang's lab examined high-speed digital video footage of a tiger beetle chasing after "prey" -- in this case, a small black bead dangled on a string serving as a dummy victim. Map out all those trajectories and you get what appears to be a tangled mess.
Wang et al. Specifically, the beetle first runs toward its prey head-on, before stopping to adjust its movement when the prey starts to "flee. It's a kind of optimal reorientation dance.
But since insects have a smaller number of neurons, their behaviors are more likely hardwired, which makes it possible for us to find and understand the rules they follow. One theory as to how the creature manages the feat is motion parallax, a common technique in used in astronomy, among other areas. The beetle's head is constantly swaying back and forth as it scuttles, which might enable the creature to focus on the prey from two different viewpoints and then determine the difference.
The other, more likely theory, he said, relies on elevation angle in the field of vision. Picture a row of chairs; the further one will appear to be the highest in your visual field.
There is some evidence that the tiger beetle shows a preference for prey at higher elevations. These are just three examples of the kinds of lessons physicists can learn from studying biological systems. Mother Nature, after all, is pretty talented engineer, with millions of years of evolutionary trial-and-error to her credit. Engels, S. Haselsteiner, Andreas F. Interface Neil, S. Solov'yov, I. Mohseni, Y. This force can be strong enough to break bones and cause organ and tissue damage.
As sports like cliff and bridge diving become more popular, fluid biomechanics research can help determine a maximum safe height for human divers and inform recommendations for positions that might minimize injury risk.
Jung and Chang are also applying their research on diving birds, supported in part by the Institute for Critical Technology and Applied Science and the National Science Foundation, to their work with a Virginia Tech senior design team on a gannet-inspired underwater projectile for autonomous sensing. Materials provided by Virginia Tech. Note: Content may be edited for style and length. Science News. New research from Virginia Tech helps explain how the birds manage these high-speed dives.
Story Source: Materials provided by Virginia Tech. How seabirds plunge-dive without injuries. New research explains. ScienceDaily, 5 October Virginia Tech.
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