eDNA Water Sampling Simulator

Place an organism anywhere in the pond and watch it swim through and vanish — leaving behind an invisible-to-the-eye trail of environmental DNA that this simulator renders as a spreading, fading cloud. The plume's concentration falls both with elapsed time (molecular decay) and with distance from where the organism actually was (dilution as it mixes through more water). Move the sampling probe to any point and moment, then take a sample: if the concentration there is still above the assay's detection threshold you get a true positive, but if decay and dilution have already pulled it below threshold, the sample comes back negative even though the species genuinely was present. Tune decay rate, plume spread rate, detection threshold and sample volume to see exactly how each one shifts the odds of catching — or missing — the signal.