Animalia · Architectonic · Photographics

Nests

Bird nests, even without knowing which birds constructed them, seem hardly possible. Creations of spider’s web, caterpillar cocoon, plant down, mud, found modern objects, human and animal hair, mosses, lichen, feathers and down, sticks and twigs–all are woven with beak and claw into a bird’s best effort to protect their next generation.

But survival for so many birds is tenuous in a modern world where habitat loss is as common as the next housing development, and even subtle changes in climate can affect food supply. It is my hope that capturing the detailed art form of the nests in these photographs will gain appreciation for their builders, and inspire their protection.

The nest and eggs specimens, collected over the last two centuries, were photographed at The California Academy of Sciences, The Museum of Vertebrate Zoology, and The Western Foundation of Vertebrate Zoology. While few nests are collected today, these nests and eggs are used for research, providing important information about their builder’s habitats, DNA, diseases and other survival issues.

The nests shown here, some collected over a century ago, were photographed by Sharon Beals. They were taken at the western foundation of vertebrate zoology in Los Angeles, which, with 18,000 specimens, now holds the world’s largest collection.

Animalia · Bio · Science · Technology

In a brainless marine worm, researchers find the developmental ‘scaffold’ for the vertebrate brain

The origin of the exquisitely complex vertebrate brain is somewhat mysterious. “In terms of evolution, it basically pops up out of nowhere. You don’t see anything anatomically like it in other animals,” says Ariel Pani, an investigator at the Marine Biological Laboratory (MBL) in Woods Hole and a graduate student at the University of Chicago.

But this week in the journal Nature, Pani and colleagues report finding some of the genetic processes that regulate vertebrate brain development in (of all places) the acorn worm, a brainless, burrowing marine invertebrate that they collected from Waquoit Bay in Falmouth, Mass.

The scientists were searching for ancestral evidence of three “signaling centers” in the vertebrate embryo that are major components of an “invisible scaffold that sets up the foundation of how the brain develops,” Pani says. Diagnostic molecular features of these signaling centers are mostly missing in the sea squirts and the lancelets, the invertebrate chordates that are the closest evolutionary relatives of the vertebrates. This had suggested that these signaling centers are key innovations that arose de novo in the vertebrate lineage.

Via Physorg