Hi Robert Are you working on materials from Cahol Pech? Leslie HARF/IMCS Hello, Just signed on to this list in hopes of tracking down some information on Pomacea flagellata. First some background, I am an archaeologist currently working on a collection from northwestern Belize in Central America. Several excavations of residences located in the outskirts of a small Ancient Mayan city encountered middens (ancient trash heaps) that were loaded with Pomacea sp. shells. These middens appear to date from between 400 B.C. and A.D. 200-300. It is fairly clear from excavations at this site, as well as others across Central America, that these are being used as a supplementary food source. Questions, 1. I am currently interested in the potential of this collection to yield paleo- environmental information. I have found some references that hint there may be a connection between environmental conditions and shell growth. Does anyone have any, or references to, information on this? (maybe stable isotope, or measurement of transverse stria?) 2. Next is a shell morphology question. Male shells develop a flange or lip around the shell opening. When does this lip begin to form? (how old is the critter when he starts growing his lip?) 3. Leading from the last question, I have seen male shells in the collection and was interested if there is a collection bias on the part of the Ancient Maya, i.e. did the Maya prefer females to males, or visa versa? As an addendum to this question I will also need to know the male / female ratio found in living populations. Any personal knowledge, references, clues or random hints in the right direction would be greatly appreciated. As far as a concrete research design goes things are still at the formative stage and will likely be shaped by any help I find here. Thanks, Robert J. Lichtenstein R. P. A. [log in to unmask]