The Effect of Gamete Competition on Levels of Gamete Production in a Marine Invertebrate

Previous work suggests that high population densities result in more intense male gamete competition and select for increased levels of production of these gametes. This hypothesis will be tested by examining spatial and temporal correlations between density and male gamete production levels in natural populations of a colonial ascidian. Two additional considerations which might modify the effect that male gamete competition has on levels of male gamete production will also be explored. First, natural selection can only act on the genetic portion of total phenotypic variance. Secondly, selection acts simultaneously on the entire phenotype, and so the effect of selection on male gamete production could be constrained by genetic correlations between this and other life history traits that are also subject to strong selection. Negative genetic correlations between male gamete production and allocation to other traits or structures would generate a trade off, with enhanced male gamete production offset by reductions in other traits. Alternatively, positive genetic correlations would constrain selection to operate on total allocation patterns as a single unit. These two potential constraints on evolution will be examined via a laboratory breeding experiment that will estimate the narrow sense heritability of male gamete production levels and explore possible genetic correlations between male gamete production and other life history traits. Overall, this study will contribute to our knowledge of the evolution of reproductive strategies in marine organisms by examining the selective pressures that fertilization processes can exert on gamete production patterns

School of Marine Sciences / Darling Marine Center

Over the last six years, the University of Maine has made an unprecedented investment in its marine laboratory, the Darling Marine Center to benefit both University faculty and visiting researchers and their students. Facility improvements include many new laboratory and offices spaces, more research instrumentation, and basic support facilities such as a dining hall and new classrooms. The inauguration of a Visiting Investigation Program in 1991, the expansion of educational offerings, and the growth of a large undergraduate internship program, have resulted in a population explosion that shows no sign of abating. To set priorities for improvements, the University has involved visiting investigators and visiting out-of-state colleges in facility planning. Based on their recommendation, housing has been targeted as the greatest facility weakness. The Center\u27s housing is primitive, overcrowed, and woefully inadequate and this deficiency is restricting the growth of both educational and research programs that impact a growing community of visiting faculty and students. The University\u27s Department of Environmental Health & Safety has issued unfavorable reports on the status of much of the Center\u27s housing, mostly due to inadequate fire protection and ADA- access. Most housing is of cottage construction and is restricted to summer use. Some housing lacks both heat and running water. In order to temporarily meet housing demand, every available space has been converted to bunk space throughout 11 separate building. Due to the age and condition of many of these structures, modernization would be largely cost prohibitive. While the Center now has beds for 60 people during the warm weathers months, year-round housing will currently accommodate only 18 students. The Center\u27s growing educational and Visiting Investigator programs are being severely hindered by this housing shortage, resulting in schedule juggling and restrictions on the number of individual s and visiting college classes that can work on site at any given time. In addition, the dining hall, built in 1992, was designed to feed 35 people at a time but now must accommodate twice that number. 20-room dormitory to house visiting faculty and students year round will be constructed. Two previous FSML facility improvements awards to the University have been responsible for stimulating the number of visiting investigators to the Darling Center and making their visits more productive. In addition, the awards have helped immeasurably to encourage additional investments by the University and by local, citizens who support the Center through their private donations

FSML: Construction of Visiting Investigator/Classroom Building at Darling Marine Center

Since 1991, the University of Maine has made significant financial investments in its marine laboratory, the Darling Marine Center to equally benefit both University personnel and visiting colleges and researchers. During 1997-99 alone, the University supported improvements including a student dormitory/dining hall. New flowing seawater facilities (construction to begin spring 2000), a new 42\u27 coastal research vessel (under construction), and more classroom microscopes and computers (delivered and in use) have also been supported. All of these improvements directly benefit visitors and they reflect a stated policy of encouraging increased use of the facilities by visiting investigators and outside colleges. Extensive marketing and word-of-mouth testimonials by visitors have resulted in a dramatic increase in visitor use of the facilities. While the Center strongly encourages visiting scientists and colleges to make use of its facilities, the growing popularity of visitor programs has resulted in a serious shortage of lab and classroom space. Educational and research opportunities for visitors are being restricted by a lack of adequate teaching and research space. The increasing demand for lab and classroom space exceeds current capacity and the facility is now unable to accommodate all potential visitors during some periods of the year. Based on several years of experience serving visitor needs, it has been learned that it is most efficient to provide flexible, multi-user space that can serve both educational and research needs. Therefore, the University will construct a 1290 sq. ft. Visiting Investigator/Classroom addition to a new Marine Culture Laboratory scheduled to be built in spring 2000. This facility will create more space for visiting scientists, it will allow out-of-state colleges to bring more students to the center, and it will make it possible for more than one visiting college to conduct courses simultaneously

Summer Undergraduate Research Fellowships at the Darling Marine Center

This award provides funding to initiate a Research Experiences for Undergraduates (REU) program at the University of Maine\u27s Darling Marine Center. The two-year pilot program will sponsor six to eight undergraduate students in an eleven-week internship that includes seminars and a research project. Mentors chosen by the students will help the students formulate and conduct a research project. Students will receive instruction in scientific methodology and related skills that are common to all fields of science (hypothesis formulation and testing, elementary statistics, experimental and sampling design, scientific writing, and data presentation). They will also participate in a seminar focused on careers in marine science and will present results of their research at the end of the program. The program is open to all U.S. citizens and permanent residents attending any college or university. Applications from women and under-represented minorities are particularly encouraged. Matching funds from the University of Maine are also included in this proposal

An Ultrastructural Investigation of Spermatogenesis in the Holopelagic Polychaetes Vanadis formosa and Krohnia lepidota (Polychaeta: Alciopidae)

Volume: 176Start Page: 123End Page: 13

Spermiogenesis and Modified Sperm Morphology in the "Seepworm" Methanoaricia dendrobranchiata (Polychaeta: Orbiniidae) From a Methane Seep Environment in the Gulf of Mexico: Implications for Fertilization Biology

Volume: 203Start Page: 134End Page: 14

ULTRASTRUCTURAL DIFFERENCES IN THE EGGS AND OVARIAN FOLLICLE CELLS OF CAPITELLA (POLYCHAETA) SIBLING SPECIES

Volume: 165Start Page: 379End Page: 39

Ultrastructure and Development of Dimorphic Sperm in the Abyssal Echinoid Phrissocystis multispina (Echinodermata: Echinoidea): Implications for Deep Sea Reproductive Biology

Volume: 176Start Page: 257End Page: 27