Hello there, interested reader.
This is my first ever blog and the main topic will be marine biodiversity, past and present. In addition to this I will post anything interesting that I learn during my studies. I hope to write this in a format that is understandable to anyone that reads it. If you have any questions regarding the content I post here, I will be more than happy to try to answer them in order to aid your understanding of the subject. I also hope to post about once a week, unless I am very busy with work.
I have recently completed a Masters project related to the origins of the present day marine biodiversity hotspot in the Indo-West Pacific. So I thought that in this first post I shall relay my main findings for you.
I have travelled to Borneo (Sabah to be precise) and have collected a large number of coral reef fossils which are now stored at the Natural History Museum in London. These fossils were accurately dated by myself and other scientists using three different methods (nannofossil stratigraphy, larger benthic foraminifera stratigraphy and strontium isotope dating). We found that the deposits dated to the late Oligocene epoch, which is approximately 30 million years b.p. (before present). This work has been published in 2011. During my project I identified around 75 different species of reef-forming coral, making this the earliest, most diverse collection of coral reef fossils from the Cenozoic era (from about 65 million years b.p. until the present day) of the Indo-West Pacific region. This collection marks the known start of the area as a marine biodiversity hotspot, since reef-forming corals of the present day are known to cover about 0.2% of the ocean floor, but harbour almost 25% of all marine species, and are therefore a good indicator taxon (taxon = a group of related organisms of a particular rank such as phylum, family, genus or species etc.) of biodiversity in a particular region.
In earlier geological time, the previous marine biodiversity hotspot was located in the Eocene (55-35 million years b.p.) the Western Tethys region (the Tethys Ocean being an ocean that existed on earth from about 240 million years ago until approximately 10 million years ago). The approximate location of this on a present day map would place it in the Mediterranean. However the Tethys eventually became cut-off from the Atlantic and Indian Oceans and dried out many times over, evidenced by the large deposits of gypsum and rock salt that can be found in the region today, hence the biodiversity here could not be preserved.
Suffice to say, biodiversity hotspots are not always located in the same areas throughout time. One major reason for this is plate tectonic movement, which can alter landforms, sea connections and climate in very drastic ways. I may write more about this in another posting, but for now I hope I have given you some insight into the geological past of marine biodiversity hotspots.
See you next week,
The Marine Invertebrate