Oysters are natural filter feeders.

FORBES: Oysters Are Back In New York City Waters

Modern evolutionary biology as we understand it, which is to say variation via genetic drift, mutations, duplications combined with the pruning filter of natural selection, certainly explains a great deal.

FORBES: Evolution and Embodied Physiology

Yet the intentionality implicit in physis is at the very core of the Darwinian concept of adaptation: forming well-functioning machines that can carry an organism through the filter of natural selection.

FORBES: Evolution and Embodied Physiology

Another tool, called Radial Filter, adjusts levels for a highlighted area while adding a gradual, natural-looking shift.

ENGADGET

The invention of the filter is a rare good news story from Bangladesh, a country so often associated with natural disasters.

BBC: Water filter set to save lives