Scott Santagata

Long Island University | LIU · Department of Biology

Evolutionary mechanisms that underlie the origins of coloniality among organisms are diverse. Some animal colonies may be comprised strictly of clonal individuals formed from asexual budding or comprised of a chimera of clonal and sexually produced individuals that fuse secondarily. This investigation focuses on select members of the lophophorates...

In some areas of the Antarctic shelf, bryozoans are abundant, acting as ecosystem engineers creating secondary structures with wide benthic coverage and harboring numerous other species. As the combined forces of global warming and ocean acidification threaten these habitats, we measured the composition of habitat-forming bryozoan communities using...

Enclosed in shells with ventral and dorsal valves, extant brachiopods (meaning –2F5;arm–2F6; and –2F5;foot–2F6;) are classified into three major subphyla–03A; the Rhynchonelliformea, the Linguliformea, and the Craniiformea. Rhynchonelliform brachiopods encompass what were once referred to as the –2F5;articulate–2F6; brachiopods, so named for the mi...

First considered to be plantlike (moss) animals similar to cnidarians, the evolutionary origin and affinities of the ectoprocts or bryozoans have been enigmatic subjects of research since the sixteenth century. The term Bryozoa originally encompassed both the entoprocts (or kamptozoans, Chap. 6) and the ectoprocts; however, these animal groups were...

Phoronids are epibenthic (or infaunal) tubiculous marine invertebrates closely related to brachiopods (and perhaps bryozoans; see Nesnidal et al. (2–013)) that have oval, U–013;shaped, or spiraling rings of ciliated tentacles called the lophophore used for feeding and respiration (Temereva and Malakhov 2–009a). Although phoronids can dominate the d...

Larval features such as the apical organ, apical ciliary tuft, and ciliated bands often complicate the evaluation of hypotheses regarding the origin of the adult bilaterian nervous system. Understanding how neurogenic domains form within the bilaterian head and larval apical organ requires expression data from animals that exhibit aspects of both c...

Phylogenetic analysis of Tt-synaptotagmin 1. Phylogram of Tt-synaptotagmin 1 and related synaptotagmin proteins, supporting the orthology assignment of Tt-synaptotagmin 1. Posterior probability for the synaptotagmin 1 clade, including Tt-synaptotagmin 1, is 100 percent (inclusive of the presumptive paralogs Mus Syt2, Mus Syt5 and Mus Syt8). The phy...

Recent structural analyses of invertebrate nervous systems have supported hypotheses stating that specific developmental and cytological aspects of larval and adult brains are conserved among bilaterian animals. Opposing views argue that structural similarities in larval nervous systems may be the result of convergent evolution and that the develop...

A matrix of 24 morphodevelopmental characters and an alignment of small subunit (SSU) and large subunit (LSU) rDNA nuclear and cox1 mitochondrial gene sequences (223C4500 sites) were compiled from up to 12 phoronids including most named taxa, but probably constituting only a portion of worldwide diversity. Morphological data were analysed by weight...

Currently, seawater flushing is the only management strategy for reducing the number of viable organisms in residual sediments and water of ballast tanks of vessels declaring no ballast on board (NOBOB) that traffic ports of the eastern United States. Previously, we identified several species of freshwater and brackish-water peracarid crustaceans a...

Regardless of the morphological divergence among larval forms of marine bryozoans, the larval nervous system and its major effector organs (musculature and ciliary fields) are largely molded on the basis of functional demands of feeding, ciliary propulsion, phototactic behaviors, and substrate exploration. Previously published ultrastructural infor...

Open-ocean ballast-water exchange (BWE) is currently the most common treatment used to reduce the ballast transfer of organisms and the subsequent risk of invasions among coastal ecosystems. Freshwater or estuarine organisms remaining after BWE often experience high mortality, due to osmotic shock caused by high-salinity exposure. We conducted 70 s...

Despite the embryological and anatomical disparities present among lophotrochozoan phyla, there are morphological similarities in the cellular arrangements of ciliated cells used for propulsion among the nonfeeding larval forms of kamptozoans, nemerteans, annelids, mollusks, and bryozoans. Evaluating whether these similarities are the result of con...

Metamorphosis (Gr. meta- "change" + morphe "form") as a biological process is generally attributed to a subset of animals: most famously insects and amphibians, but some fish and many marine invertebrates as well. We held a symposium at the 2006 Society for Integrative and Comparative Biology (SICB) annual meeting in Orlando, FL (USA) to discuss me...

Phoronis pallida (Phoronida) occurs as a commensal within the burrow of Upogebia pugettensis (Decapoda: Thalassinidea). Upogebia-conditioned seawater (UCSW) induced an exploratory swimming behavior in competent larvae of P. pallida in a dosage-dependent manner. This behavior included a significant increase in swimming speed that was directed downwa...

Morphological variation among larval body plans must be placed into a phylogenetic and ecological context to assess whether similar morphologies are the result of phylogenetic constraints or convergent selective pressures. Investigations are needed of the diverse larval forms within the Lophotrochozoa, especially the larvae of phoronids and brachio...

The structure of the larval nervous system and the musculature of Phoronis pallida were studied, as well as the remodeling of these systems at metamorphosis. The serotonergic portion of the apical ganglion is a U-shaped field of cell bodies that send projections into a central neuropil. The majority of the serotonergic cells are (at least) bipolar...

A comparative analysis of the larval and presumptive juvenile neuromuscular systems among actinotroch larvae was performed using confocal laser microscopy with probes for F-actin and serotonin. Currently, there are two main categories of larval nervous systems based on the origin of the nerve fibers that innervate the larval tentacles. Characterist...

Scrupocellaria ferox forms erect colonies whose budding pattern is similar to that of early fossil encrusting cheilostomes, except that peripheral lateral buds are suppressed into heterozoids, and stolons and flexible cuticular joints are present, presumably as a requirement of the erect colony form. The ovicell of S. ferox is a flattened chamber c...

Membranipora chesapeakensis n. sp. was collected on wood substrate in the Ches-apeake Bay, Maryland. Colonies are erect, vermiform or ribbon-shaped to bilaminar, with two back-to-back layers sharing one basal cuticle. There is a minute cryptocyst and a beaded gym-nocyst; zoids have 14 tentacles and lack knobs or other decorations in their corners....