Current Research
Small Title
Figure: Penn et al., 2018, depicting their model of temperature-dependent hypoxia as a driver of the end-Permian marine mass extinction.
In the past 0.5 billion years or so, several cataclysmic events, known as mass extinction events, have swept through the globe and nearly wiped out life itself. With the exception of outlying mass extinctions such as the one triggered by an asteroid impact, most of these events were predominantly triggered by volcanic eruptions that choked the atmosphere and oceans with massive amounts of carbon and sulfur. In turn, the ocean became more acidic, global oceanic temperatures skyrocketed, and oxygen levels depleted, all resulting in a huge toll in taxonomic abundance.
Rifling through the record of life to see how ecosystems have responded to changing environments can help us to better predict how modern marine ecosystems will fare as a result of the current climate crisis.
I do so using a combination of field work in Saudi Arabia to reconstruct benthic seafloor communities, and coding using fossil data from the Paleobiology Database (pbdb) and the R software.
I took this image of an ancient home just outside Riyadh city in Saudi Arabia
I drew this graphical abstract for a paper I coauthored to explain how we examine patterns in past extinction events (and the recovery of ecosystems afterwards) with processes related to organismal physiology and changes in oceanic temeperature and oxygen. Much of the work I do involves investigating potential links of biogeographic recovery patterns of benthic marine ecosystems to these physiological concepts.
![Selectivity of mass extinctions-4[88].png](https://static.wixstatic.com/media/f339c1_145bb3e0c0774a4989ee75fac966a306~mv2.png/v1/crop/x_0,y_0,w_2239,h_2250/fill/w_118,h_118,al_c,q_85,usm_0.66_1.00_0.01,blur_2,enc_auto/Selectivity%20of%20mass%20extinctions-4%5B88%5D.png)
My work mainly involves marine invertebrate fossils, namely mollusks such as clams and snails, since they are globally widespread and have a rich stratigraphic record, which means that their preserved fossils span much of the 542 million year history of visible life.
Along with biogeographic and paleo-ecological analyses, I am training to taxonomically identify bivalves (ex: clams), gastropods (ex: snails) and brachiopods from my study area and period. These are not my study specimens, but I snapped a pic of these lovely fossil bivalves during a trip in Capitola beach, CA. These fossils are 5 million years old!
My father, a retired stratigrapher who worked on the stratigraphy of the same site I am sampling my fossils from (40 years ago!), lent his expertise in the area and collaborated with us on one of my projects in Saudi!
