Molecular dynamics

Icicles hang from the mermaid with dolphin in the Beatty Memorial Fountain by William McMillan and Edwin Lutyens in Trafalgar Square, Westminster, London, United Kingdom. Photo: Leon Neal/Getty Images.

One Flew Over the Cuckoo’s Nest

A Harris’s hawk sits on the Nelson’s Column in Trafalgar Square in London, England. Photo: Facundo Arrizabalaga/EPA.

Bid–ask matrix

London, England: The new sculpture on Trafalgar Square’s fourth plinth, “Really Good” by David Shrigley, has been unveiled. Photo: Daniel Leal-Olivas/AFP/Getty Images.