The bivalve Arctica islandica is the longest-lived non-colonial animal known to science. It  can be found on continental shelves across the North Atlantic down to Virginia at the western Atlantic coast and to the Barents Sea in the east (Begum et al., 2009), where it can tolerate a wide range of different environmental factors (salinity, temperature, oxygen availability) (Basova et al., 2012). The oldest individual ever observed in this species was found Northeast of Iceland with an age of more than 500 years (Butler et al., 2013). A. islandica populations offer a promising opportunity for ageing research, such as the examination of the telomere dynamics with age. The species demonstrates indeterminate growth with very low growth rates compared to other bivalves (Begum et al., 2010; Strahl et al., 2007; Witbaard, 1996) and a constant rate of cell proliferation in many different tissues (Strahl and Abele, 2010). 

A. islandica is found in habitats with extremely different environmental conditions and populations exhibit large variations in maximum lifespans (Basova et al., 2012). Recent studies in marine bivalve molluscs have revealed an association between longevity and resistance to multiplex stressors (oxidative, genotoxic stress) as well as between longevity and proteostasis in several species including A. islandica (Treaster et al., 2013; Ungvari et al., 2013a; Ungvari et al., 2011; Ungvari et al., 2013b). Remarkably no enhaced antioxidant capacity or protein recycling was detected compared to shorter-lived species (Ungvari et al., 2011) but a higher ability to withstand different environmental stress factors in general was observed (Abele and Philipp, 2012; Basova et al., 2012; Philipp et al., 2012).  It is hypothesized this may greatly be influenced by the animals‘ energy allocation to tissue maintenance, growth or reproduction. A deeper understanding of telomere dynamics and other variables with respect to longevity and environmental influences in organisms may be attained by the investigation of the remarkable long-lived bivalve.

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