In all likelihood, it could have lived for much longer. The 507-year-old quahog, named Ming, only met its end because it was frozen after its capture to allow researchers to properly determine its age. Buildup of these molecules can cause damage to DNA, RNA, and proteins and result in cell death.ĭue to the quahog’s attenuated amount of these reactive oxygen species, it is able to fight off a common source of aging and live for many centuries. The secret to this longevity is linked to the quahog’s unusually thin production of reactive oxygen species, which are unstable and oxygen-holding molecules (aka free radicals). This would put its original birthday sometime in 1499. Even more, those rings offer insight into its life-with wide rings showing a year of plentiful food and narrow rings showing a scarcer time.ĭue to this trait, one ocean quahog was dated to 507 years old-the oldest of its kind ever found. Like a tree, its life span is recorded in the growth rings of its shell. This marine bivalve mollusk is special because it is exceptionally easy to determine the creature’s age. Planarian worms and their stem cells are somehow able to avoid the aging process and to keep their cells dividing.ĭue to this cellular youth, flatworms defy aging, making it difficult to accurately measure a flatworm’s life span. This means that the stem cells are no longer able to divide and so become less able to replace exhausted specialized cells in the tissues of our bodies. Usually when stem cells divide-to heal wounds or during reproduction or for growth-they start to show signs of aging. Aziz Aboobaker of The University of Nottingham commented: But one cause of this remarkable feat may not have been mentioned in our high school classes.ĭr. Recently, a lab at MIT performed an experiment that regrew an entire flatworm from a single cell. Our school classes taught us about the special regenerative powers of the flatworms, unassuming creatures that harbor the ability to regrow into two healthy flatworms if cut in half. The biologists reported, “In a number of cases, such multicellular aggregates may result in a full reconstruction of an animal’s initial organization.” These amazing regenerative abilities render these creatures nearly ageless. The key to their longevity may lie in their simplicity.Īndrey Lavrov and Igor Kosevich, biologists who studied marine sponges’ abilities, found that when the sponges were subjected to tissue dissociation (by mechanically or chemically separating the cells from one another), the sponges were able to re-form into their original shape. Yet a marine sponge specimen has been found to be at least 11,000 years old, with some studies suggesting the potential life span of these creatures to be in the hundreds of thousands of years. They have no internal organs, digestive tracts, or nervous and muscular systems. They don’t possess the common elements that other animals (like us) have in abundance. Both TOBEC and TBW measurements are relatively easy methods of tracking qualitative changes in body composition within individuals, but TBW should be used when quantitative estimates of nonpolar lipid mass are desired.As far as multicellular animals go, marine sponges are as simple as they come. A sensitivity analysis suggests that, in most cases, TBW can be used to estimate nonpolar lipid mass within 15% of actual lipid mass. When total nonpolar lipid mass was greater than 0.1 g, the average percent error in predicted nonpolar lipid was 30% and 15% for the TOBEC and TBW methods, respectively. Estimates of nonpolar lipid mass, derived by subtracting predicted wet lean mass from total body mass, were highly correlated with actual nonpolar lipid mass. Regression models based on either TOBEC or TBW were able to predict dry lean mass and wet lean mass within 5% of actual values. I validated the use of total body electrical conductivity (TOBEC) and total body water (TBW) to estimate lean mass and nonpolar lipid mass in the lizard Sceloporus undulatus. However, most methods have proved to be either difficult or inaccurate for estimating lipid mass, particularly in small animals. Nondestructive methods of estimating body composition are crucial for measuring energy budgets of free-ranging animals.
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