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Natural history collections (NHCs) are an important source of the long-term data needed to understand how biota respond to ongoing anthropogenic climate change. These include taxon occurrence data for ecological modeling, as well as information that can be used to reconstruct mechanisms through which biota respond to changing climates. The full potential of NHCs for climate change research cannot be fully realized until high-quality data sets are conveniently accessible for research, but this requires that higher priority be placed on digitizing the holdings most useful for climate change research (e.g., whole-biota studies, time series, records of intensively sampled common taxa). Natural history collections must not neglect the proliferation of new information from efforts to understand how present-day ecosystems are responding to environmental change. These new directions require a strategic realignment for many NHC holders to complement their existing focus on taxonomy and systematics. To set these new priorities, we need strong partnerships between NHC holders and global change biologists. [ABSTRACT FROM AUTHOR]

A thiarid gastropod, Vinundu westae new genus and new species, is described from Lake Tanganyika, and the species Nassopsis guillemei Martel & Dautzenberg, 1899 is transferred to this new genus from Edgaria (= Lavigeria). The shell of Vinundu has equal axial and spiral macrosculpture, producing characteristic regular nodes at the sculptural intersections. Reproduction in Vinundu is oviparous, in contrast to the ovoviviparous habit of its sister group, Lavigeria. Radular teeth and isotope values indicate that this is a grazer. Vinundu species are readily distinguished from their sister clade Lavigeria by conchological, anatomical and molecular characters. The two Vinundu species are common in deep water, rocky habitats of this clear-water, ancient lake. [ABSTRACT FROM AUTHOR]

In the study of gastropod shell morphology, determination of comparable ontogenetic stages is crucial, because all the states that various shell features go through during ontogeny are preserved on the shell. The protoconch/teleoconch transition and marks of episodic growth are among the few ways of defining discrete, comparable, growth stages. In gastropods with determinate growth the attainment of adulthood may provide additional shell markers permitting comparison among individuals and taxa. Adulthood is reflected in shell morphology in ways as diverse as shell deposition covering all the previous whorls and radically changing the shape of the shell through to slight changes in the trajectory of the suture. While the very prominent adulthood-related changes of shell morphology have been used as systematic characters, the more moderate changes have not been studied in detail and their potential systematic value has been ignored. In this paper we give a detailed account of adult modifications of the shell appearing with cessation of growth. Our study group comprises eight closely related species of Lavigeria from Lake Tanganyika. We show that the ways adulthood is manifested are quite diverse. We describe eight characters of the aperture, the suture and the sculptural ornamentation. Character occurrence varies greatly among species. We show that characters appear in suites and that in many cases their appearance is connected to size. We use size as a proxy for adulthood and test whether character occurrence alone or its connection to size can help resolve species relationships. In both cases our characters confirm the monophyly of our ingroup and yield cladograms with various degrees of resolution of ingroup relationships. The coding method that yields the greater character congruence is the one that takes into consideration the connection between appearance of a character and size. This study demonstrates that ontogenetically correlated character transformations may nevertheless be phylogenetically independent. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 140, 223−240. [ABSTRACT FROM AUTHOR]

The article presents the research study "Two new highly polymorphic microsatellite loci and inadvertent minisatellite loci for Lymnaea auricularia." It mentions that microsatellite loci are useful for tracing the populations' genetic histories for its high mutation rates while minisatellite loci are useful in detecting variation among species. It also notes that the use of microsatellite primers in population genetics marks the importance of species-specific development of genetic tools.