If you ’ve ever bailed on a nose dive and terminate up performing abelly flopfor all to see , you ’ll have a unique appreciation of the force presented by water supply surface tension . Diving beast experienceenormous pressuresduring water entry , which is followed by the formation of an air tooth decay and finally a splatter as this closes . These shock personnel can be minimized by create a hydrodynamic form as you enter the urine ( aka , not a belly fizzle ) , and such soundbox type are vulgar among dip - diving seabird .
Perhaps one of nature ’s most telling frogman is theNorthern Gannet , Morus bassanus , who stars in the opening bait chunk sequence in David Attenborough ’s tardy exit , A Perfect Planet . These hardy seabirds will follow a pod of dolphins until both parties find some food for thought , which in A Perfect Planet fall out to be a pleasant-tasting shallow of mackerel .
As the dolphins begin to pick away at the fish , they form a bait ball that gets pushed towards the sea control surface as a means of trapping the mackerel . Here , they enroll Gannet territory , as the birds start arrive at the piddle like feathered fighter planes , some reaching speeds of 24 cadence ( 78.7 foot ) per second . They can plunge up to 11 meters ( 36 foot ) and float further to view fish , which they drag to the surface by beat their net foundation and wing . Performing such a hunting scheme would for sure import tragedy for a human being , so how are these birds capable to hit the sea surface with such ferocity without snapping their farsighted , svelte necks ?
The resolution is a shining exercise of development drive by the survival of the fittest . To carry out their ecological recess , gannet have evolved to have highly specialized neck , which field of study say would n’t experience harm until diving at a whopping focal ratio of 80 beat ( 262.5 feet ) per secondly .
To investigate how such raspberry can survive diving into the water system at such speeds , a subject release inPNASused a salvaged bird head to discover the hydrokinetics of dip - diving event . Their investigations revealed that there were anatomical feature of the skull and cervix muscular structure which , combine with exist birds ’ chosen diving speeds , can stabilize this weak and slender body part during dip - nose dive .
When firing their deceased Northern Gannet ’s head through the water aerofoil vertically at just about 5.5 meters per second , they were able to identify the impact , cavity shaping , and splash phase of a plunge dive . The impact phase is when the beak first makes middleman with the pee , followed by the cavity stage which organize a sort of bubble around the hiss as its head becomes amply submerged .
This phase is interesting , as the bird ’s brain is now decelerating while the quietus of its body stay on to speed up . The research worker conclude that fowl are able to survive what could be a fatal densification of the neck thanks to muscle that are bunch around the skull . By contracting these , they can brace their neck long enough for the razz ’s chest to score the water which mark the end of the compressing stage . This , combined with the doll ' chosen diving speeds which stay within a range that wo n’t crush their cervix , sees the gannets firing into the water like feathered arrows .
The researcher bode that a gannet would need to enter the water at around 80 meters ( 262.5 feet ) per second to sustain an injury which , for citation , is around double the maximum pep pill limit in the United States . Not bad , Northern Gannet . However , there is a limit to their neck stabilizing acquisition .
