See inside a sea spider!
/Legs as lungs and guts as hearts!
These videos show peristaltic movement of the gut in the legs, which act as a pumping heart to move blood around the spiders' bodies.
Legs as lungs and guts as hearts!
These videos show peristaltic movement of the gut in the legs, which act as a pumping heart to move blood around the spiders' bodies.
We are using flip tests to study the effects of water temperature on capacity for activity in sea spiders. Flip performance declines at warmer temperatures, which provides insight into potential effects of global warming upon these polar giants.
After diving at Cape Evans Wall, we visited the Scott Hut at Cape Evans. This hut served as the base of operations for the shore party of Robert F. Scott's Terra Nova expedition from 1911-1913. Persistent cold, dry air preserves the contents such that one has the impression the explorers walked out only a short time ago, headed for the pole.
A year-long experiment using sea spiders at McMurdo Sound to test whether the use their ovigers to control the growth of epibionts on their cuticle.
The cuticle of sea spiders is often colonized by a wide variety of micro and macro organisms. Part of our research is testing what effect these "epibionts" have on sea spider respiration and biomechanics.
Some sea spiders adopt a posture that resembles a comet when they are descending in the water. In aquaria in the lab, smaller species readily exhibit the behavior, but larger species do not. We are conducting experiments to test the functional significance of cometing, to understand whether it is relevant to the ecology and evolution of these creatures.
In October we experienced a Condition 2 storm at McMurdo Station. Condition 2 features one or more: wind speed between 89 and 102 kilometers per hour, wind chill between -59 and -73 degrees Celsius and visibility less than 400 meters. It was not a day for travel on the ice!
Although the above-ground environment around McMurdo seems harsh and lifeless (except for some charismatic vertebrates), life in Antarctica's oceans is diverse and abundant. The problem is how to get to it through the sea ice. Here we show the process of drilling a hole for SCUBA and what you see when you dive through it.
We waited five extra days while in Christchurch, New Zealand. The weather at Pegasus Airfield in Antarctica was unfavorable for landing a plane. We became familiar with 4:30 AM phone calls indicating renewed 24-hour delays. To our great enthusiasm, on October 7th the call came indicating the flight was a go. C-17 Globemasters are remarkably loud inside (everyone wore hearing protection), and it is fascinating to see exposed ventilation, hydraulic and electrical lines that are normally covered from view inside commercial jets. Our first view from a small port-side window of the vast ice of Antarctica was humbling and awe inspiring.
During the first half of 2015, we were trained as scientific divers under the supervision of Dive Safety Officer Pema Kitaeff at Friday Harbor Labs, part of the University of Washington. The labs are on San Juan Island, near the coast of Washington, USA. In June, we used SCUBA diving to collect sea spiders from hydroids, we brought them back to the labs, and we studied aspects of their biology.
Our team arrived in Christchurch on September 30, and the next day went to the CDC to pick up our 'ECW'--extreme cold-weather gear. It's a lot of stuff--about 22 lbs of it! We'll take it all to McMurdo with us, and we'll wear a lot of it on the flight down.
In the US Pacific Northwest, pycnogonids typically grow to maximum diameters of only a few centimeters. They feed on soft-bodied, sessile organisms, such as hydroids, anemones, and sponges. We collect pycnogonids on SCUBA (see video on right).
It's hard to see and collect small pycnogonids, which usually are well camouflaged (Fig 1). We therefore collect hydroids and other potential foods, bring them back to the lab, and look for pycnogonids using a dissecting microscope (Fig 2).