Knowledge, Attitudes, and Factors Associated with Organ Donation Willingness among Adults in Lebanon.

The phenomenon of age appears as a characteristic of virtually all complex organisms spanning both botanical and zoological domains. Whether aging is viewed as beginning at an embryonic stage of life or at some later point, it represents a near-universal phenomenon across species. For many animals, this generally applies whether the focus is on ontogenetically programmed sequential changes (e.g., fecundity), on molecular damage or other biochemical processes (e.g. shortening/breaking of telomeres; keratinization of ocular gland ducts), on mechanical wear and tear changes (e.g. wearing teeth and joints; cumulative exposure to sunlight) or other factors. Such processes occur while debates continue in areas such as the relative importance of purely temporal processes vs. counts of cell division (e.g. []) and the role of factors such as immune responses and diet [, ]. While many of these concerns and issues relate to processes of aging across the life world, in this paper we focus on age and aging specifically in humans, which embody key distinctive features compared to the aging and developmental processes of other species. Because much of gerontological science does little to recognize this and assumes continuities between the study of other forms of life and the human sciences, we begin by examining the clear evidence for human distinctiveness. Despite sharing much of our genome and organismic features with a multitude of living genus and species, from beetles to coyotes, human aging is distinctive and in some key ways unique, even among primates. It is marked by patterns not seen and processes not experienced in the lives of other species.