Worm mothers provide milk for their young

As worm mothers age, they secrete a milk-like fluid through their vulva that is consumed by their offspring and supports their growth, according to a new study led by UCL researchers. Scientists say the discovery, published , shows both a selfless and sacrificial act, and helps to explain a number of mysteries about the biology of ageing in the nematode worm Caenorhabditis elegans , widely studied to understand how organisms age. Lead author Professor David Gems (UCL Institute of Healthy Ageing) said: "We have now explained a unique self-destructive process seen in nematode worms. "It is both a form of primitive lactation, which only a few other invertebrates have been shown to do, and a form of reproductive suicide, as worm mothers sacrifice themselves to support the next generation." Most C. elegans , a one-millimetre long transparent roundworm, have both male and female reproductive organs, so the mothers reproduce by fertilising themselves with limited stocks of self-sperm. When these run out, within days of sexual maturity, reproduction ceases. The worms then behave in a way that has puzzled scientists for some time: they generate large quantities of yolk-rich fluid which accumulates in large pools inside their bodies, destructively consuming internal organs in the process. They also lay more than their own body weight in unfertilised eggs.