My Research: Cyprus’s Marine Palaeoecology

nicfmThe map above shows the geology around Nicosia, from 5 Ma to the Quaternary. The green boxes are Pliocene fossil localities, with dominant fossils labelled. There are many more localities and many more fossils, I’m just using it as an example for the bulk of my palaeontological work here.

This work is documenting the fossil diversity in these localities in a palaeoecological context. Each locality’s stratigraphy is mapped, and the invertebrate macrofossil contents (identified as much as possible to species level) of each layer documented and put into a GIS-referenced database. The species assemblage for each layer gives an idea of the palaeoenvironment, since the type of ecosystem can be inferred from the species’ ecologies. The layer succession tells us about environmental changes and events that took place in time.

The next, much harder, step is to correlate these fossil localities together, to see when each layer was deposited. When done, this can lead to several interpretations, two of which are of interest to me:

  • If layers are deposited at the same time, then we have the spatial aspect. A layer with shallow water fauna 5 km away from a deep-water layer from the same time means we can trace the continental slope or detect an ancient basin.
  • If layers are deposited at different times, then we have local events affecting the ecosystems, meaning we can get a glimpse at the complexity of the oceanography around Cyprus 5-2 million years ago.

The potential insights gained range from local geology to regional and Mediterranean-wide marine evolution.

On the geological side, it’s known that Troodos, the main mountain of Cyprus, has gone through several pulses of uplift, including one in the Pliocene that continues to now. By having a high-resolution look at the fossil palaeoenvironments, it may be possible to calculate the rates of uplift, by tracing the changing ancient coastline of Cyprus.

But I’m most interested in the evolution of the Mediterranean’s marine biology. The start of the Pliocene in the Mediterranean is marked by a crucial event: the end of the Messinian Salinity Crisis and the restoration of marine conditions. The Messinian Salinity Crisis happened when the Straits of Gibraltar closed the Mediterranean off from the Atlantic, turning it into a gigantic lake that eventually evaporated (kilometer thick gypsum and other evaporite layers attest to this); the Straits opened again at the start of the Pliocene, and the Atlantic flooded back in, complete with a faunal recolonisation.

Studying how animals successively colonised the Mediterranean is a potentially exciting question, needing detailed dating of layers from all over the Mediterranean, to see if the recolonisation was “instant”, or if there was a pattern with some taxa – following circulation patterns, perhaps.

Only the comparison between pre-Messinian and post-Messinian biodiversity is interesting by itself, and Cyprus is perfect for this, since the marine fossil record is continuous from 50+ million years ago, including the macrofossils I study. Of course, this needs similar work done on the older stuff, and that’s the natural extension of this work.

Finally, there are also younger localities, including of archaeological age, and what this allows is a direct comparison of these ancient palaeoenvironments with the environments found off the coast today. For this aspect, I collaborate with marine biologists to explore various ecological aspects, such as predation intensities and species interactions, through time.

There is also the possibility of giving a deep time perspective on the severity of the Lessepsian Migration – the highly-successful migration of Red Sea fauna into the Mediterranean through the Suez Canal – although marine biologists were careful enough to do censuses of marine life on both sides before the canal was opened.

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  1. Pingback: A quick-and-dirty geological summary of Cyprus | Teaching Biology

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