Inference of ecology from the ontogeny of microfossils
Schweitzer, Peter N.
MetadataShow full item record
LocationSippewissett Marsh, Buzzards Bay, MA
Sierra Leone Rise
This work comprises three detailed studies of ontogeny and ecology. In the first chapter, four living species of the ostracode genus Cyprideis were studied both morphologically and ecologically to determine whether differences in age at maturity are correlated with heterochrony as expected; accelerated maturity should yield generalized morphology and small size, while delayed maturity should produce specialized morphology and large size. Two of the four species show the expected pattern, the other two do not. Cyprideis does not support the generalization that life-history evolution causes heterochrony, and casts doubt on the inference of life-history evolution from heterochrony where the data are drawn exclusively from extinct forms. In the second chapter, populations of Globorotalia menardii and G. tumida were subjected to careful morphological analysis; the stable-isotopic composition of the growth stages revealed that both species inhabit the upper fifty meters of the ocean, descending to deeper water (75-l00m) for the emplacement of an enveloping calcite crust. The third chapter shows a simple relationship between proloculus size and rate of chamber expansion in the polar planktonic foraminifer Neogloboquadrina pachyderma. The consequences for morphology of variations in ontogeny can be used to suggest ways of selecting specimens that minimize ontogenetic variations in shell chemistry.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 1989
Suggested CitationThesis: Schweitzer, Peter N., "Inference of ecology from the ontogeny of microfossils", 1989-06, DOI:10.1575/1912/5395, https://hdl.handle.net/1912/5395
Showing items related by title, author, creator and subject.
A radiocarbon method and multi-tracer approach to quantifying groundwater discharge to coastal waters Gramling, Carolyn M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2003-09)Groundwater discharge into estuaries and the coastal ocean is an important mechanism for the transport of dissolved chemical species to coastal waters. Because many dissolved species are present in groundwater in ...
Tarrell, Alvin E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1997-09)Saltwater marshes and wetlands are important buffers at the land-sea interface. Among the most biologically active ecosystems on Earth, natural and man-made wetlands are important interceptors of pollutants and nutrients ...
McNichol, Jesse C. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2016-09)Chemoautotrophic ecosystems at deep-sea hydrothermal vents were discovered in 1977, but not until 1995 were free-living autotrophic Epsilonproteobacteria identified as important microbial community members. Because the ...