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Visual Adaptations in Hyperiid Amphipod

The amazing eyes of hyperiid amphipods defy reason. With everything from no eyes though, simple pigment cups, cylindrical eyes, eyes with crystalline cones that function like fiber optics, extra pairs of eyes, eyes that take up their entire head, blinders made of exoskeleton, and mirrored eyes this suborder of crustaceans are an amazing group to study how midwater animals have adapted to the unique challenges of this largest habitat on earth. In this project we are using an integrative approach that combines studies of visual physiology, behavior, phylogenetic history, transcriptomics, neurobiology, and oceanography to ask questions like what can individual species see, how do their visual capabilities relate to their habits (depth, associations with gelatinous zooplankton, migration, free-swimming or symbiotic), and how have their visual traits evolved over time. Primary collaborators include Jamie Baldwin Fergus, Sonke Johnsen, Bill Browne, and Daphne Soares. Baldwin et al. 2015

Deep-sea acorn worm biology

The Torquaratoridae are a group of deep-sea acorn worms first described in 2005 and since, observed all over the world ocean’s sea floor. They are abundant, morphologically diverse, as acorn worms go, large, often colorful, and instead of living in burrows in sediment, they live out of the surface of the deep sea floor or drifting above it. They are found on soft sediment to fresh lava flows. We are working to describe the major clades within the Torquaratoridae, their unusual reproductive biology, their behavior, and their evolutionary history. Primary collaborators include Nick Holland, Linda Kuhnz, Ken Smith, and Jessie Whelpley.

Tomopterid worm biology

Tomopterid polychaetes are some of the most beautiful animals in the midwater. They can be large (reaching well over a foot in length). They are diverse (with approximately xx described species), active predators found throughout the entire depth of the midwater. Little is know about their biology and they are difficult to identify, especially when alive. By collecting them, photographing key characteristics and taking tissue samples for genetic work, we are sorting out the different species and their distributions, generating characters that will allow identification of them when alive, and building a phylogenetic reconstruction of their evolutionary history in order to study evolution of their unique yellow bioluminescence. We are also studying their biomechanics. My primary collaborator on the project is Kakani Young and Jessie Whelpley.

Cirratuliform worm diversity

Several large swimming worms, which were all more closely related to each other than any other known worms, were discovered in deep-water over the past 10 years. Several have been described including Swima bombiviridis (the green bomber), Swima fulgida (the shining bomber), Swima tawitawiensis (the orange bomber), and Teuthidodrilus samae (squidworm) but many remain to be described and named. This group is particularly interesting because it contains a range of species, some are completely benthic, others are completely pelagic, and still others spend part of their time on the seafloor and part in the water column. Because of this range of lifestyles, they are an excellent group to study adaptations to and changes in morphology and behavior when transitioning from benthic to pelagic lifestyle. They are also large, abundant animals that likely have a large impact on the communities they are a part of and are thus ecologically important animals. Osborn swima 2011.pdf

Munnopsid isopod natural history

The unusual crustacean family Munnopsidae contains the majority of free-living, pelagic isopods. They are extremely abundant in the deep-sea and nearly exclusive to this habitat. In contrast to the typical uniform body of isopods, munnopsids have specialized legs and body segments. Three of these specialized pairs of legs are used to swim backward through the water and two to three other pairs are extremely elongate and used for parachuting, striding and particle collecting. The movements of these animals, particularly their swimming and elongate legs are a fascinating example of automated and largely passive movement. We are interested in many aspects of their biology including their feeding habits, describing the many undescribed species, and their diversification patterns. If the right collaborator could be found, we would love to study their biomechanics. Osborn 2009.pdf