Field Collection: Animals

Abstract

Biologists interested in population genetics, systematics and conservation need to collect representative samples before starting laboratory work. The way such collections are made depends very much on the particular research topic. For example, a molecular systematist studying deep-level phylogeny needs only a few individual samples from each of the species of interest, a conservation biologist needs to collect samples from across the species’ distribution range in order to study the genetic diversity of the organism, while a molecular population biologist needs to collect random samples from each population studied (preferably individuals from different localities of the same population) to investigate population structure, dynamics and phylogeography. The choice of molecular techniques used subsequently in laboratory analysis will determine, to a large degree, the amount and type of tissue required and the preservation methods used in field collection. Nevertheless, it is commonly recommended that collectors maximize quantities of as many tissue types as is feasible and use cryopreservation wherever possible. For example, if RFLP and RAPD analysis are planned or there is a need to construct a genomic library for isolation of single copy nuclear sequences, great care must be taken to prevent DNA in the tissue from being degraded in order that high molecular weight DNA may be isolated. If PCR-based techniques are going to be employed, such as PCR-RFLP, SSCP or PCR sequencing, collectors may be more relaxed about preservation, as both the quality and quantity of DNA isolated are not as crucial and may be less than optimal for analysis by these methods.