Latest Research

March 1, 2017

What did Classical Greek and Roman society do to the environment they inhabited? In 2018, we will launch the "Empire Expedition"--a research cruise to the eastern Mediterranean.  This cruise will unite an international team of archaeologists, historians, paleontologists and marine geologists for an integrated study of the impact of growing human societies on their environment.

February 15, 2017

I and a team from the Smithsonian Tropical Research Institution have been coring reefs in Panama and Belize to see how human activity has changed the reef.  One of our findings is that parrot fish have dramatically declined on Panama reefs over the past century.  It turns out that removal of the parrot fish (which we can see by looking at the abundance of well preserved parrot fish teeth in reef sediment) is closely tied to the health of a reef.  The more parrot fish, the faster the reef grows!  To find out why this is so, check out our video and new research paper.....

May 26, 2016

I recently participated in International Ocean Discovery Program Expedition 361--the "African Safari"--to drill off SE Africa to recover a record of African climate and ecological evolution during the time humans, and out ancestors, were evolving on land. Here are a couple videos that talk about the cruise, from what I expected to find to what actually happened on the cruise.

October 28, 2015

Open-ocean sharks in decline for the past 20 million years

August 25, 2014

An enduring mystery in Geology is why and how rocks move of their own accord over a nearly flat, mud-cracked lake bed in Death Valley National Park--the Racetrack Playa. We set up the "Slithering Stones Research Initiative" in 2011 to find out.  With NPS permits in hand, we set up a weather station, and outfitted 15 rocks with GPS loggers to record when they moved, how fast they went and where they went. This past December, Jim Norris and I saw them go, and our GPS trackers recorded what they did. Now we have a paper in PLOS ONE  that tells the curious tale of the wayward rocks of Death Valley!  This is a free download thanks to my paying for open access:

We also have a couple videos that show what we saw....See:


March 13, 2014

Among my interests is the evolution of zoogeography in the oceans, particularly in plankton but also in corals.  I have been working for several years on the puzzle of how foraminifera repeatedly re-invade the Atlantic from the Indo-Pacific during interglacials  after driven extinct in the Atlantic during glacials. And it is not just foraminifera that show these extinctions, but also large billfish like Black marlin to some kinds of pelagic snails. These serial local extinctions and re-invasions suggest that the oceanography of the Atlantic and the Pacific oscillate out of phase with each other.  We think that at least part of the explanation is the evolution of the thermocline in the Atlantic. 

The video link is obviously not me but highlights the remarkable similarities between different places! Also, my vehicle of choice is more likely to be a ship than a car, but I like the humor.  My work focuses on what is different about the Atlantic and Pacific that control the composition of oceanic biodiversity.

August 2, 2013

If we do nothing to move away from our fossil fuel economy, in less than 80 years, the world will experience ecological disruptions like those last seen during rapid climate change events in the "Greenhouse world" 40-60 million years ago. Both the geologic record and models of the future Earth show that these ecological shifts will persist for at least 20,000 years (and with a recognizable human 'fingerprint' of >100,000 years), creating a constantly shifting version of what we consider "normal" about our environment. Hear the NPR piece with Richard Harris:

March 18, 2013

In early March I visited the Bremen core repository for the IODP Expedition 342 "sample party"--a week of drinking great German beer and cutting up cores from early in the morning to late at night.  About 40 scientists from all over the world ended up taking some 30,000 samples for a plethora of post-cruise scientific studies. Even so, we managed to leave a couple kilometers of sediment in the cores for later work!  Look at the U-Tube video to hear about the repository and what really went on at the 'party'. See:

February 6, 2013

Part of the science party for IODP Expedition 342 “Paleogene Newfoundland Sediment Drifts” (gathered around the sampling table with the Cenomanian-Turonian boundary).  Inset: The JOIDES Resolution on station. See for videos of our cruise.

February 6, 2013

Left: Field photograph of the Bocas del Toro Field Station in NE Panama.  Right: An example of the fish teeth recovered from modern reef sediments (grid is 2 mm).