After touching on the concerns of natural scientists about biodiversity loss, this article argues that it is a mistake to believe that there are only losses of biodiversity. The process of changes in the stock of biodiversity is more complex. Furthermore, it is pointed out that not all genetic material is an economic asset. Also, it is contended that not all genetic material is natural. Some of the genetic stock is of a heritage type and a portion has recently been developed by human beings. Improved conceptualisation of the stock of biodiversity is needed. Some of the ways are listed in which economics is relevant to issues involving biodiversity conservation. General economic factors, such as market extension and economic growth, which result in loss of genetic diversity among domesticated organisms are outlined. China’s recent experience with biodiversity loss highlights the importance of these factors. Some important reasons why economic factors result in biodiversity loss in the wild are identified and reasons are given why economic systems conserve less biodiversity than is ideal. Before concluding, the subject is discussed of what genetic material and other components of biodiversity should be conserved given economic constraints on what can be conserved.