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that settling invertebrate larvae do not avoid settling near established dominant
competitors.
It is probable that post-selective forces other than pressure tolerance may exist,
such as suitability of habitat or food availability, which eliminates juveniles of
Asterias rubens and Marthasterias glacialis outside the adult range.
The plasticity on the early-life story stages, therefore their ability to tolerate
increasing pressure may be cumulative over many generations, until an individual
species has successfully adapted to the deep-sea environment. It is possible that this
adaptation may have been rapid as a number of deep-sea invertebrate species retain
the seasonal growth and reproductive patterns seen in shallow water congeners
(Young 2003).
3.5- Recommendations
It is recommended to design a method to measure the pressure experienced
inside the plastic vials at the same time as they are located inside the pressurized
chambers in order to corroborate that the pressure experienced outside and inside the
plastic vials and therefore experienced by the developing embryos is the same.
It is important to perform experiments comparing the effects of pressure on
early embryos and larvae using rapid release of pressure and also slow decompression
rates, to determine if the depressure/repressure event observed in the present study
have a possible effect on the embryos development.
Stumm et al. (2001) studied the effect of elevated pressures with rats in
laboratory simulating the effects of the high pressure neurological syndrome (HPNS).
Their results showed that animals subjected to 61 bars with slow increase in pressure
and around two hours of constant high pressure followed by a rapid decompression
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