Page 16 - BBC Wildlife Volume 36 #04

WILD NEWS

RIES
DISCOVER

Written by
STUART
dom.
The latest in scientific research from all over the animal king d BLACKMAN

Seagrass is on the
menu for the veggie
bonnethead despite
having a gut that is
Q MARINE LIFE typical of a meat-eater.
SHARKS THAT EAT THEIR GREENS

VEGETARIAN BONNETHEAD SHARKS MAINLY FEED ON PLANT MATERIAL AND ARE ABLE TO DIGEST IT.

harks are surely the last bonnetheads can DID YOU KNOW? Leigh of the University She is currently investigating
animals you’d expect to thrive on a 90 per of California, the source of the plant-digesting
Q Another unlikely
Senjoy their vegetables. But cent seagrass diet. vegetarian is the Irvine. “We know enzyme. Her suspicion is that
bonnethead sharks are ableto They are ableto break tropicalAmerican that the scalloped it is produced by mutualistic
get byon littleelse. down the vegetable jumping spider hammerhead, a micro-organisms living in the
Back in 2007, it was matter by means of an Bagheera kiplingi, very close relative of bonnetheads’ guts.
whichfeeds almost
discovered that up to 62 per enzyme in their guts – the bonnethead,is There isalso the matter of
exclusively on nectar
cent of the gut contents of these missing in carnivorous and the protein- carnivorous, despite what this quirky foodchain
sharks was plant material from animals–that targets rich leaf tips that thriving in similar means for the ecology of the
their preferred seagrass meadow theplants’ tough cell Acacia plants use to regions andhabitats.” seagrass meadows. “Bonnethead
attractthe ants that
habitat. What wasn’t clear was walls. What’s more, the Plankton-feeding sharks are abundant in seagrass
protect them from
whether the sharks reap any biologists showed that herbivorous insects. species such as meadow habitats,” says Leigh.
nutritional benefit from all that the digested material sharks, which inevitably ingest “However, the role that they are
basking and whale
becomes incorporated into the
salad. It was speculated that
playing is unclear now that we
Beth Swanson/Shutterstock their short guts – typical of an sharks’ body tissues. significant quantities of algae know they are not acting as the
toppredators.”
exclusive meat-eater – might not
mightalso provideclues. “We
So is it possiblethat omnivory
even be able to digest it.
do not know the extent towhich
has been overlooked in other
planktivorous sharks can digest
predatory shark species? “It’s
It turns out that they can.
SOURCESocietyforIntegrativeandComparative
Biologists have now found that
16 BBC Wildlife hard to say,” says Samantha phytoplankton,” Leigh says. BiologyLINKhttp://bit.ly/2EAxSzS April 2018