BIODIVERSITY AMONG HAPTOPHYTE ALGAE

The division Haptophyta is represented only by about 300 extant specie s showing wide diversity in morphology, biochemistry and ecology. They have a world-wide distribution and are numerically important in phyto plankton populations in nearly all marine environments. Evidence from the geological record shows that they have been the major constituent of calcareous deposits since the Late Triassic and, as they have evolv ed quickly through time, their coccoliths have always shown wide morph ological diversity. In today's oceans they occasionally produce extens ive blooms, visible by satellite imagery, which have ecological impact . As a consequence of these blooms the haptophyte algae are now receiv ing greater attention, as their role in the global sulphur and carbon cycles may influence the world's climate, and their potential as nuisa nce bloom algae have implications for commercial fishing and the marin e ecosystem. As it is likely that these organisms have always produced such blooms, these effects may have been in operation for the last 20 0 million years.