It's high time I outlined our group's research objectives for this season. Chances are this will ask for more than one installment. As the title of this post suggests, several disparate-but-strongly-related research strands are being followed, one of the ultimate intentions being to find both the distinguishing features and the connection points between each one of them so that the relationships between them can be woven together to form a more complete overview. People are working independently, collaboratively, across speciality areas and disciplines. Each person in Team G-093 brings something unique and essential to the mix; I think we'd all agree that as a group, we'll be able to accomplish more together than we could if we stood alone. So far, it's proving to be a season of rich pickings.
I can't possibly go into all the intricacies of the various projects here, but I'll start by synthesizing what I've come to understand so far, drawing additionally on spoken or written input from the three Principal Investigators - Sam Bowser (cell biologist), Molly Miller (geologist) and Sally Walker (taphonomist*). First, let me introduce you to these three scientists -
- Sam Bowser is a veteran polar biologist. His first research trip to the ice was in 1984; he has spent a further twenty-six seasons in Antarctica studying the morphology and motile behaviour of foraminifera ~
- One of the major motivations behind Molly Miller's work is the 'inherent mystery of it all' - the not-knowing. From where I stand, it seems to me that the process of investigation is every bit as captivating for each of these investigators as the elusive destination might be.
- Sally Walker, the taphonomist in the group, is down here for the first time but is no novice to field research, having conducted numerous fossil-related studies in unusual sites such as the Galapagos Islands, Mexico and Sapalo Island, Georgia. Here she is discussing the labeling of arrays with diver Henry Kaiser. (You can tell from the way Henry's holding Sally's scallop array that when he's not diving, he's very likely to be found playing his guitar!)
In a nutshell, the group's driving observation has to do with the fact that while the Antarctica sea floor is teeming with life, there is virtually no record (body fossils or burrow bioturbation**) available for interpretation through the Cenozoic sediment sampled just offshore. What processes cause this disjunct? How can the Explorers Cove sediment and contained life be used to elucidate the Cenozoic environment recorded in cores?
Experiments are being conducted in and around Explorers Cove to determine (1) if shells and skeletal material dissolves, and if so, how fast? (2) to identify specific characteristics of New Harbor sediment, its mode of delivery to the sea floor and the rate of sedimentation (important when it comes to interpreting the relative density of animals and shell material, and assessing the rate and record of bioturbation, and (3) the rate of bioturbation by infaunal animals***. The group's intention is to evaluate these determining characteristics in different areas and by so doing, to ascertain whether concerns (1), (2) and (3) differ from one area to the next. (This explains the need for multiple dive holes, and for there being three major sites at reasonable geographical distance from each other).
Additional work is being done using the information gleaned from the above key questions, including the development of a mathematical model that effectively simulates the sedimentary record, thereby allowing for comparisons to be made between new material and existing sequences found in cores. Related questions include the following:
(1) What is the rate of deposition?
(2) How is the sediment transported?
(3) What is living in the local sediment, how does it churn the sediment and at what rate?
(4) How abundant are the different species of foram?
(5) What is the fate of shell material? (focusing in on adamussium colbecki - Antarctic scallops - foramanifera and ophiuroids)
(6) What are the oceanographic, sedimentologic and biologic characteristics at each of the sites - and why?
(7) How effectively can chemical analyses pertaining to pH, salinity, dissolution rates, etc... be conducted?
(8) Sedimentologic investigation is an important study component - i.e. examining and documenting grain size from short cores as well as from the existing datastore.
(9) Re; biological concerns - the group has been conducting a quadrant census on surface sediment, documenting the presence or absence of scallops, ophiuroids and other animals (important data for comparison with debris in cores)
(10) Observation of infaunal populations
(11) Site surveys are being carried out as documentary evidence of research settings.
- One of Molly's mini-sediment aquaria: displacement of the fluorescent pink sand will be an indication of bioturbation.
- Cores used to gather sediment for Molly and/or forams for Sam
- Adamussium colbecki - Antarctic scallop
- Astrammina Triangularis - agglutinated foram
Last, but not least, there's the outreach component that runs adjacent to each of these projects, which is where the art comes in (1) in its own right as a conceptual medium and method of communication, (2) in its collaborative ArtScience capacity where it plays a powerful advocacy role on behalf of science and re: the Antarctic continent in general, and (3) as a bridge-builder connecting the dots between research areas and disciplines. Ideally, in this context, the art will act as a catalyst making art more accessible to scientific audiences, and at the same time conveying the wonders of science to a wider creative public. (I'll say more about this in a subsequent post.)
Molly Miller (who has spent seven seasons working in Antarctica on various geological projects, including Andrill) emailed me the following paragraph in response to my questions about her work in the Explorers Cove environment;
'I am so excited to be in Explorers Cove finding out more about life on the ocean bottom. Amongst other things, our group will be exploring the taphonomic filter between present-day organisms and bioturbations, together with the fossil record in coves. We hope also to determine the mode of sediment transport and the rate of sedimentation. Skeletal material from ophioroids will be suspended in the ocean for up to two years and the disintegration and skeletal dissolution rate of bioturbation will be determined by putting known numbers of burrowing animals into custom-made laminated sediments (mini-aquaria) then uplifted for x-raying two years later (during the 2010 season). Sediment traps will also be used to document rates of deposition and grain size, and surface-texture analysis will be used to determine infaunal modes of transport.'
It might be best for me to stop here, at least for the time being. This is rather a looooong post. I'll pick up where I left off just as soon as time and camp activity allows.
Before I go, though, here's a brief glossary of terms in case it's helpful. I've certainly had to refer to the dictionary often during this field season!
* Taphonomy is the branch of paleontology that deals with processes of fossilization.
** Bioturbation is the disturbance of sedimentary deposits by living organisms.
*** Infaunal refers to the animals living in the sediments of the ocean floor or river or lake beds.
~ Foraminifera are ancient uni-cellular aquatic organisms of which there are four main types: naked, thekate (soft-walled), agglutinated and calcereous.