LittleNeck_clams_USDA96c1862
Figure 1. The ocean quahog clam.

How long do they live? Hundreds of years and one in particular named Ming was found to be 507 years old [1]. He was killed in 2006 by the scientists who were trying to study his cells. So, earning the title of the worse scientists I’ve read about, they popped open a creature that was born during the Ming Dynasty, ensuring that we will never know how long he would have lived. Telomere length does not seem to be associated with their extreme lifespans [2], but high superoxide dismutase activity may be some of the reason they age so well [3].  Superoxide dismutase is an enzyme (a protein that does work) that helps break down oxygen molecules that are hell bent on damaging cells and tissues. These clams are also very slow growing and it’s thought that they have a very efficient cellular damage response [4].

Where are they found? The North Atlantic Ocean.

What do they eat? They’re filter feeders, so they filter plankton out of the water that they suck in.

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Figure 2. Atlantic quahog clam

What do they look like? A clam (or a giant clam if you happen to be the now deceased Ming). See figures 1 and 2.

How do they reproduce? Like us they use eggs and sperm. Unlike us, they release those eggs and sperm into the water for fertilization. Larvae grow until they become too heavy to float and they fall to the ocean floor to burrow in the mud. They don’t really move much from that spot either. Quahog clams reach sexual maturity around 20 years of age [6].

How do scientists know how old they are? By counting the number of bands on the clam shell [5].

So what are we lacking? There’s no information regarding the nuclear genome of Arctica islandica on NCBI (National Center for Biotechnology Information) . That’s kind of a shame given a creature that was 507 years old died for science. There is, however, information on the NCBI regarding the mitochondrial genome.

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Not every clam makes it to old age.

Conservation status: Not evaluated by the IUCN Red List, but may be vulnerable due to water quality.

 

  1. Butler, Paul G., et al. “Variability of marine climate on the North Icelandic Shelf in a 1357-year proxy archive based on growth increments in the bivalve Arctica islandica.” Palaeogeography, Palaeoclimatology, Palaeoecology 373 (2013): 141-151.
  2. Gruber, Heike, et al. “Telomere-independent ageing in the longest-lived non-colonial animal, Arctica islandica.” Experimental gerontology 51 (2014): 38-45.
  3. Abele, Doris, et al. “Imperceptible senescence: ageing in the ocean quahog Arctica islandica.” Free radical research 42.5 (2008): 474-480.
  4. Strahl, Julia, et al. “Physiological aging in the Icelandic population of the ocean quahog Arctica islandica.” Aquatic Biology 1.1 (2007): 77-83.
  5. Ocean Quahog, Arctica islandicaJ. W. Ropeshttp://www.nefsc.noaa.gov/fbp/age-man/oq/oq.htm
  6. Ocean Quahog. Islandic Fisheries and Agriculture Council. http://www.fisheries.is/main-species/invertebrates/ocean-quahog/  Accessed 12/17/2016.