A robin built its nest in Fred Margulies' backyard, and he filmed a flurry of activity over a period of four weeks, during which four tiny blue eggs became four tiny babies. Spring is pretty adorable. Video below.

Johanna Mårtensson's bread city is an examination of what happens to modern cities after human inhabitation ends, and the structures are left to the will of nature. Of modern metropolises, Johanna thought, "Within 500 years all buildings would be half-fallen or fallen, perfect homes for animals and plants. The forest would soon grow in cities. Afterhand, buildings as well as pollutions would be taken care of by bacteria and micro-organisms. A UFO that came here in a couple of hundred thousand years would not see many signs that a gang of primates once thought that they were the lords of the planet."

To demonstrate the natural state of submission to the elements, Mårtensson bult a bread city, which she photographed over a period of six months to observe its decay and the "creation of a new process," through which the city would belong not to humans, but to micro-organisms.

The amazing precision with which Ellie the goshawk flies through this obstacle course will impress you, and probably make you a little envious. There's no way I could mold my body so incredibly, a feat which the first comment on this video summarizes: "Elly seems able to mould her body to any shape - I'd like to see her make a cow."

Marc Martin illustrates a beautiful adventurer's guide to the alphabet, starring exotic animals. Martin also includes a map of where to find the strange creatures, and interesting facts about them. I don't know if anyone is supposed to have a favorite letter of the alphabet, but that loris might be the star of the series.

A laborer works at a salt production factory in Nangqian county, northwest China's Qinghai province, on July 24, 2007. (Reuters/Simon Zo)

The Atlantic brings us this collection of salt mines from all over the world, each with its own strain of strangely alien beauty, and a long history which is deeply tied to local culture. Each salt mine is shaped by different geographical elements and varying levels of access to modern technology.

From Dutch art group Observatorium, Warten auf den Fluss (Waiting for the River) is part architectural art exhibit, part environmental protection, designed to celebrate the rehabilitation of the Emscher River. Once considered biologically dead from years of waste materials, the river is expected to be in good health by 2020. The habitable bridge which will eventually overlook the river, is 125 feet long and includes enough space for long walks, naps, and picnics.