Aloha Conchers,
In Hawaii Pustularia takahashii started appearing in the fossil records at
the 15ft level(roughly 150,000yrs ago). Same level where 2 endemic
species, Conus kahiko & Strombus ostergaardi, disappeared. Commonly found
at this level to present strata are Conus pennaceus & Cypraea maculifera
hawaiensis. During this era the Hawaiian Islands were much closer to the
Equator due to plate techtonics. One would think the North-Eastward plate
movement towards colder waters might have have changed the local species.
This means the water temperature gets colder as time goes on & some
species may die-off while others establish themselfs.

Look at Lambis chiragra. This species prefer warmer temperatures & was
present in Hawaiian fossil records 150,000yrs ago. Today no chiragra
occurs in Hawaii. Could the colder waters restrict veliger developement?
Or could the location of the islands in comparison to the Equator limit
the veliger range of dispersion & settlement from other Indo-Pacific
Islands? One must also consider the ocean level 150,000yrs ago in Hawaii
was 15ft higher before the last ice age. Also 1.5 million yrs ago small
Midway Atoll was a large major mountaneous Hawaiian Island roughly where
Oahu is today.                             CHRIS:)

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