Genetic tools are a major part of modern comparative biology. Museums are the place where much of this sort of research occurs as museums are storehouses of the source material used in comparative genetic studies. Frozen tissue is stored in ultralow freezers or in liquid nitrogen for a variety of organisms comprise genetic resource collections or GRCs. Ideally tissue samples should be associated with a voucher specimen such as skeletal material, a stuffed skin or a pickled specimen. This allows researchers to check the identity of the tissue sample or compare genetic data with morphological data derived from the source specimen. In ornithology there is a growing trend to collect a blood or feather sample from a bird and release the bird back into the wild. A digital photo together with carefully taken morphological measurements can serve as the voucher for the blood sample. While this is not the "gold standard" way to build a bird collection it can augment traditional collecting efforts and increase numbers of samples while minimizing the effect of collecting on avian populations. Below is a video of me collecting a blood sample from a House Sparrow (Passer domesticus) caught just outside the Geier Collections and Research Center at Cincinnati Museum Center. When done properly there is no evidence of adverse effects on the bird, even though surely it is not an experience they enjoy!