

Now that we have shown you lifespan quantification in worms, let's examine how it is done in fruit flies. The animals should be transferred to fresh plates every 2-3 days to avoid starvation. Remove dead worms and record the number of dead and live worms. For older worms, it might be necessary to gently prod the worm's head to elicit a response. Over the course of the experiment, to determine if worms are alive or dead, the plate can be tapped to observe worm movement. To measure worm lifespan, these larvae are transferred to plates containing the drug FUDR, which suppresses worm reproduction without affecting adult lifespan. Once a sufficient number of eggs are acquired, the adults are removed from the plate, and eggs are incubated at 20☌ for 2-3 days to allow the worms to hatch and grow to the L4 larval stage.

On this food-rich environment, the dauer larvae will resume their life cycle and become reproductively mature young adults.įinally, after two days these adult worms are transferred onto another fresh plate and allowed to lay eggs for up to 24 hrs. Some of the worm larvae that are starved will enter a hardy, growth-arrested state called "dauer." Then, these dauer larvae are moved to a fresh plate. To do this, first worms are left on the same culture plate for approximately one week, allowing them to consume all the available food, and thereby inducing starvation. Briefly, these experiments involve collecting parent worms, synchronizing the age of their progeny, treating larval worms with a drug to inhibit reproduction, and finally transferring worms to test plates and counting worms that are dead or alive.Īt the start of the procedure, it is necessary to obtain a sufficient number of age-matched animals by synchronizing a batch of worms to all lay eggs at the same time. Now that we've learned why invertebrate models are highly amenable to aging studies, let's look at how experiments to measure lifespan are performed in worms. They are also quite amenable to genetic manipulation, with many available tools that allow specific genes to be turned on or off easily to observe their effects on the aging process. To study these factors, researchers have been taking advantage of the short generation times of invertebrate model organisms, such as worms and flies, which allow scientists to observe multiple generations over days or weeks, rather than months, as in the case of mammalian models such as mice. Diverse factors, including radiation and chemical damages from the environment, and toxic byproducts from our own metabolic processes, have all been suggested to play a role in aging. Scientists don't yet completely understand why organisms age. Meanwhile, most animals would naturally stop growing, even in ideal conditions, after which they will age or "senesce" until dying. Some organisms, like many plants, might theoretically live forever.

Lifespan is the amount of time that an organism lives and functions, between birth and death. Before looking at the experimental procedures for measuring lifespan, it's important to first understand what is lifespan and aging.
