Progression into the sand coincides with
large pressure pulses and is facilitated by the
secretion of a large amount of mucus. Contrary
to popular belief, the lingula pedicle
is not used for burrowing; it is unable to dig
into the sediment. Instead it acts as a support
or prop while repeated scissor like movements,
shell closure with water injection, and
shell openings accompanied by pressure
pulses result in successively deeper penetration.
Burrowing follows a semicircular
course, the radius of which probably depends
on shell size. The animal burrows obliquely
downward to a depth that has not yet
been established in natural conditions, then
curves upward and burrows vertically until it
reaches the surface of the sediment. Pedicle
anchoring following burial is achieved by
mucoid adhesion of sand and various particles.
Some fossil U-shaped burrows could
be related to re burrowing features (EMIG &
others, 1978). While reentering the sediment
the animal is extremely susceptible to
predation.
Progression into the sand coincides withlarge pressure pulses and is facilitated by thesecretion of a large amount of mucus. Contraryto popular belief, the lingula pedicleis not used for burrowing; it is unable to diginto the sediment. Instead it acts as a supportor prop while repeated scissor like movements,shell closure with water injection, andshell openings accompanied by pressurepulses result in successively deeper penetration.Burrowing follows a semicircularcourse, the radius of which probably dependson shell size. The animal burrows obliquelydownward to a depth that has not yetbeen established in natural conditions, thencurves upward and burrows vertically until itreaches the surface of the sediment. Pedicleanchoring following burial is achieved bymucoid adhesion of sand and various particles.Some fossil U-shaped burrows couldbe related to re burrowing features (EMIG &others, 1978). While reentering the sedimentthe animal is extremely susceptible topredation.
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