Ichthyology

Friday, March 25, 2011

The Oarfish Omen

Oarfish

A week before the earthquake and tsunami hit Japan, an omen washed up on its beaches. The appearance of the oarfish, a ribbon-like, deep sea fish has long been perceived as a warning that seismic activity is on the way. This fish has become a feature of speculation as to whether they can be used to predict an incoming earthquake.

There are many news reports that speculate on the issue, as well as impressive photos of this critter, which can reach lengths in excess of 50 feet.

The important message here is that so little is known about the habits, breeding, biology, and ecology of these fishes – and deep water species in general. It is difficult to say what they are reacting to – small tremors signaling a larger quake to come, poisonous gases released by shifting tectonic plates or perhaps water temperatures affected by subtle movements in these plates. So little is known about deep water fish species due to the difficulty involved in studying them in their natural environment. They do not survive long (or act erratically/unusually) in shallow water, making it difficult to glean anything about their behavior based on these shallow water sightings. Their natural environment, depths below 1000 feet, is the place to study them, only possibly by using submersible or Remotely Operated Vehicles (ROV’s) but these tools are very expensive and not very numerous.

It is estimated that we have only described about a quarter to half of the species in the deep oceans. Who knows what lives down there and what sort of interactions they have with their deep water environment, as well as what sort of future events they may be able to sense before we know anything about them?

It is also interesting that local folklore (dismissed or ignored by many in the scientific community) says that these fish appearing in shallow water signal not only an earthquake, but also a good catch! These two are likely related in that tremors or earthquakes will scare or force deep water fish into the shallows.

Wednesday, August 22, 2012

Molecular Analysis Confirms Morphological Analysis

The Aug. 6 edition of the Proceedings of the National Academy of Sciences  included a large-scale analysis of bony fishes using DNA sequencing. One of the major conclusions is that tarpons, eels and their relatives (Elopomorpha) is the sister group (branched first) of all living teleosts.

Gloria Arratia, research associate in ichthyology, first published this idea in 1997 (see reference 11 in the PNAS paper). Her conclusion was based on morphology. In short, molecular analysis  confirms a careful morphological analysis conducted about 15 years ago. More interesting is the fact that Gloria’s results were not widely accepted because the dominant figures in the field had championed the idea that the Osteoglossomorpha (mooneyes and bonytongues) were below the tarpons and eels on the tree. This inhibited some other ichthyologists from accepting Gloria's findings, in spite of the fact that she had the evidence and presented it clearly. 

—Ed

Wednesday, September 7, 2011

Waste Not, Want Not

fish

Like any good ichthyologist, I keep saltwater fish.  When I lost a Banggai cardinalfish recently, how did I deal with this tragedy? Not by flushing it or starting a pet cemetery, but by turning that loss into a gain for the Biodiversity Institute's Ichthyology collection. 

It is true that aquarium fish make less than ideal specimens.  It is impossible to get accurate, reliable information on the natural habitat, behavior, distribution, and population structure of such a specimen.  However, for large-scale genetic studies, a specimen without such data can still provide valuable insight into the evolutionary relationships among fish species.  Likewise, we can gain important morphological information to further inform our ideas on the evolution of structures like jaws and tails.

So how does a fish reach scientific immortality after passing on to the great aquarium in the sky?  First, and not surprisingly, it's important to get the fish into the freezer as soon as possible to keep it from decomposing (genetic material starts to break down quickly as the fish decomposes).  When we are ready to process the fish, we first take photos of it, since preservation often causes bright colors and patterns to fade. Then a small piece of muscle is taken from one side and added to our tissue collection--this leaves the other side of the fish intact for morphological studies.  We then inject the fish with formalin and store it in alcohol, or clear and stain it.

While at first blush this may seem perverse, my cardinalfish now lives on as frozen tissue and fluid specimens, where it will provide valuable genetic and morphological information for researchers and students.  I know I would much prefer that to being flushed.

Saturday, May 29, 2010

Introducing Hannah Owens

Hannah OwensHannah Owens is an Ichthyology graduate student at the University of Kansas in the Biodiversity Institute.  She is particularly interested in the role of climate change in the evolutionary history and biogeography of fishes, especially cods.  Hannah will be travelling to Kangerlussuaq, Greenland for a week as part of KU’s Climate Change, Humans, and Nature in a Global Environment (C-CHANGE) National Science Foundation Integrative Graduate Education and Research Training (IGERT) program.  She and her fellow trainees (in diverse disciplines ranging from sociology and anthropology to history and engineering) will be investigating the multifarious effects of climate change in the Arctic.

Friday, June 11, 2010

Greenland Wrap-Up

Leaving Greenland

And so, a scant 10 days after it began, my Greenlandic adventure is at an end. I got to experience big polar science, witness the first suggestions of climate change in the form of retreating glaciers and early mosquito and flower emergence, and eat some delicious whale and cured fishes of many sorts.

Three highlights:

Camping near the ice edge.
Talking arctic science with grad students from other universities.
The Søndrestrom Incoherent Scatter Radar Facility.
Three things I still can’t wrap my head around:

I met the U.S. Ambassador to Denmark.
The ice sheet is huge. Really, really huge.
I went to Greenland?!

It was a fun trip, both too short and just long enough. Until my next adventure, kasuuta and takuss!

—Hannah

Thursday, June 10, 2010

The Final Sprint

Our final day in Greenland was best characterized by last-minute good intentions and chaos as we tried to do everything we had been putting off all week. After breakfast, we visited the Kangerlussuaq Museum. As we were driving up, the man who is the museum (ticket taker, curator, and docent) ran up and greeted us enthusiastically and followed us around asking if we had any questions and telling us all about the history of the army base and airstrip known as Kangerlussuaq. One gets the impression that his summers (he goes back to Denmark in the winter—there isn’t a lot of activity once the snow and darkness set in) are usually spent in quiet contemplation of the photos documenting the comings and goings (glamorous actresses, well-known politicians, and eminent scientists--Niels Bohr once sat on the porch outside!), the history of aviation, polar science and the military in and out of Kangerlussuaq, and the occasional rogue wildlife that has wandered in from the tundra (including the skin of the only documented polar bear from the area and photos and cartoons of “Terrible Willie”, the musk ox that held Kangerlussuaq in his sway, often thwarting capture attempts and running amok on the runway and through the streets).[ibimage==694==310-scale-rounded==none==self==ibimage_img-left]

After that enlightening stop, a few of us did some sight-seeing, including driving up to the TACAN radar station, which offered great views of Kangerlussuaq, as well as the surrounding tundra and lakes. While up there, we ran into an international group of wealthy tourists (accompanied by a police escort) that were taking a “study tour” of Greenland, including several men in dress shoes wielding very nice birding telescopes and fancy SLR cameras and several women in precarious heels that were much more interested in picking an herb that looked like rosemary and smelled like Lysol to steep for aquavit. It was a little surreal.

We came back for lunch, wrapped up souvenir shopping, and returned all our glass bottles to collect the deposit. This involved feeding each bottle onto a conveyor belt with a scanner that counted and verified that the bottles were the appropriate size. It was very cool, and made me once again yearn for a similar system in Kansas. Once business in town was wrapped up and all the students and professors were rounded up, we ran back out to the tundra, where Sharon Billings, KU’s Ecology and Evolutionary Biology professor on the trip, taught us about how tundra soil forms, including mechanical and chemical weathering, as well as decomposition (which is MUCH slower in the Arctic than elsewhere, since colder temperatures impede the metabolism of bacteria that do the decomposing). We then ran back to pack and eat dinner. After dinner, there was more packing, hunting down equipment we had borrowed from KISS, and socializing with the other scientists passing through Kangerlussuaq on the way to or from fieldwork.

The next day was a lot of hurry up and wait with the Air National Guard before getting on the C-130 back to the States—it was a straight shot back, since it is the beginning of the field season and much more equipment is being flown into Greenland than out. I got to go up in the cockpit, which was awesome—there is a ridiculous amount of equipment and space up there, including a bunk where one of the crew members was taking a nap. Dinner was a much-anticipated slice of pizza at New York Pizza and Fried Chicken in Schenectady—it turns out I really missed pizza! The following day, Thursday, was another day of travel from Schenectady to D.C. to Kansas City on United Airlines regional jets that made me long for the freedom of a C-130, where you can get up and move around as much as you like. Up next, the wrap up. 

—Hannah

Monday, June 7, 2010

Ungulates and Undulating Ice

Caribou

Today was full of wow! It was another day of driving, hiking, sun, and awe in the vicinity of Russell Glacier. On the way there we spotted our first real live musk ox, an enormous hairy mound of beast that seemed to remind everyone either of Snuffleupagus, a bantha from Star Wars, or Ludo from Labyrinth. This was followed by our first caribou, a young one with tiny velvety nubs of horns that ran toward us, around us, and off to the river again.

We stopped for lunch at part of the glacier that ends in a pool which emptying out into the river next to a really nice beach. The wind off of the glacier was bitterly cold, but once we got within fifty meters of the glacier, it blocked the wind and made plopping down on the glacial till for a sandwich and a Coke absolutely lovely. We sat around for awhile waiting for the glacier to cave, but no such luck. Extra-special bonus: first Gyrfalcon of the trip!

Hannah Owens

As we drove on, we also spotted a flock of what else but Canada geese. Kind of annoying, since we see them all the time at home, but neat since they were the first Greenlandic Canada geese of the trip (does that make sense?). We also spotted another duck, this one closer and in better light, but still from a moving car—my guess would be a male pintail, but I may correct that in a later post…

At last, we arrived at a spot from which we could hike out onto the glacier. At first, it looked like huge, random piles of gravel and mud, but as we went father, jumping across a shallow stream, the crunch of ice underfoot and the suddenly visible infinity short snowy spires and cliffs let us know exactly where we were. There was an abundance of melt-water streams with tasty cold, clear water—unusual this early, or so I'm told. The two professors on the trip that had previously visited the glacier commented that they had never seen streams this large or plentiful on the glacier before. We also found a moulin, or glacial mill, which is a large funnel in the ice where melt water streams drain onto the glacier bed below. Tomorrow we're camping, so I’ll be taking a brief hiatus. Cheers!  

—Hannah