Camouflage–adaptations that prevent detection and/or recognition–is a key example of
evolution by natural selection, making it a primary focus in evolutionary ecology and animal …

A new kind of optics has grown up during the last 25 years. Geometrical optics has been
studied for centuries (the law of reflection was known to the ancient Greeks) and wave optics …

We examine the nature of the stationary character of the Hamilton action S for a space-time
trajectory (worldline) x (t) of a single particle moving in one dimension with a general time …

An experimental method is presented that detects whether a droplet is spherical. The
method is based on a comparison between two droplet diameters deduced from two …

In shallow water, downwelling light is refracted from surface waves onto the substrate
creating bands of light that fluctuate in both time and space, known as caustics. This …

Many animals avoid detection or recognition using camouflage tailored to the visual features
of their environment. 1, 2, 3 The appearance of those features, however, can be affected by …

Highlights•Environments contain dynamic features, which introduce visual noise.•Visual
noise reduces the signal-to-noise ratio and can mask conspicuous signals.•Movement of …

Natural habitats contain dynamic elements, such as varying local illumination. Can such
features mitigate the salience of organism movement? Dynamic illumination is particularly …

An optical technique for tracking single particles has been used to evaluate the particle
diameter at which diffusion transitions from molecular behaviour described by the fractional …

Highlights•Caustic flicker is a common type of visual noise in shallow aquatic habitats.•We
tested whether caustic flicker impairs the hunting success of cuttlefish.•Caustic flicker did not …