Tuesday, September 11, 2012

Iridescent berries

Iridescence is well-known in the animal kingdom (and has been around since at least dinosaur times), but this-- the African herb Pollia condensata-- seems to be the first known example of an iridescent plant:

From Not Exactly Rocket Science, which explains the physical basis and possible evolutionary significance of this phenomenon.

Monday, August 20, 2012

Golden tortoise beetle


Image from 9wows, via Pharyngula.

Also, according to Wikipedia:
They can change color, looking initially like tiny jewels, or golden ladybugs, but can alter the reflectivity of the cuticle so the outer layers become clear, revealing a ladybug type of red coloring with black spots. This color change is accomplished by microscopic valves controlling the moisture levels under the shell.

Thursday, June 28, 2012

Mesozoic coastlines and modern politics

Virgil once wrote, "Felix qui potuit rerum cognóscere causas"-- "Happy is the one who knows the causes of things," and I am certainly happy to know the cause of a band of Democratic-voting counties in the otherwise mostly Republican Deep South, namely that this geographical region used to be the coastline of an ocean that split North America during Cretaceous times. Intermediate links in the causal chain are plankton, chalk, cotton, and slavery:
During the Cretaceous, 139-65 million years ago, shallow seas covered much of the southern United States.   These tropical waters were productive–giving rise to tiny marine plankton with carbonate skeletons which overtime accumulated into massive chalk formations.  The chalk, both alkaline and porous, lead to fertile and well-drained soils in a band, mirroring that ancient coastline and stretching across the now much drier South....
Over time this rich soil produced an amazingly productive agricultural region, especially for cotton.  In 1859 alone a harvest of over 4,000 cotton bales was not uncommon within the belt. And yet, just tens of miles north or south this harvest was rare.  Of course this level of cotton production required extensive labor...
As Washington notes further in his autobiography, “The part of the country possessing this thick, dark, and naturally rich soil was, of course, the part of the South where the slaves were most profitable, and consequently they were taken there in the largest numbers."

Tuesday, June 26, 2012

Ctenoimbricata

Believe it or not, this odd prickly creature, which lived during the Cambrian era, is a primitive echinoderm:

Echinoderms (starfish, sea urchins, sea cucumbers, crinoids, etc.) are well-known for their pentamerous (5-fold) radial symmetry. ...Many living echinoderms pass through a bilateral larval stage, evidence for the well-worn adage "ontogeny recapitulates phylogeny" (also known as the Biogenic Law, which as a general hypothesis is now largely unaccepted). However, no fossil evidence - that is, an actual bilateral echinoderm - has ever been found (although a few asymmetric fossil echinoderms are known). Until now. Samuel Zamora, of The Natural History Museum in London, and colleagues have just described Ctenoimbricata spinosa, a new genus and species from the Murero Formation (earliest middle Cambrian Period) in northeastern Spain.
Via This View of Life.

Friday, May 11, 2012

Thursday, March 29, 2012

Waterbirds

Cormorant
Mallards, domestic ducks, hybrids thereof, and a coot

 Coots on the march

Thursday, January 26, 2012

Sand, magnified

These grains include what looks like a tiny crustacean's claw, a minuscule shell, and spines possibly from a sea urchin. Image from Nikon Small World.

Friday, January 20, 2012

Siphusauctum

Over a century after its initial discovery, the Burgess Shale continues to be a treasure trove of bizarre Cambrian fossils, most recently this tulip-shaped creature:
Reconstruction by Marianne Collins
“Most interesting is that this feeding system appears to be unique among animals. Recent advances have linked many bizarre Burgess Shale animals as primitive members of many animal groups that are found today, but Siphusauctum defies this trend.  We do not know where it fits in relation to other organisms,” said lead author O’Brien.
Via Life Before the Dinosaurs.

Tuesday, January 17, 2012

Fossils from Darwin's cabinet

A "treasure trove" of fossils - including some collected by Charles Darwin - has been re-discovered in an old cabinet.
The fossils, lost for some 165 years, were found by chance in the vaults of the British Geological Survey HQ near Keyworth, UK.
...
The find was made by the palaeontologist Dr Howard Falcon-Lang.
Dr Falcon-Lang, who is based in the department of earth sciences at Royal Holloway, University of London, spotted some drawers in a cabinet marked "unregistered fossil plants".
"Inside the drawer were hundreds of beautiful glass slides made by polishing fossil plants into thin translucent sheets," Dr Falcon-Lang explained.
"This process allows them to be studied under the microscope. Almost the first slide I picked up was labelled 'C. Darwin Esq'."
From BBC News. The Daily Mail has more pictures.

Sunday, January 15, 2012

McMurdo Sound, Antarctica

Underwater mcmurdo sound
This image of an ice wall and the ocean floor at Explorer's Cover, New Harbor, McMurdo Sound is adjacent to remote-controlled photographic equipment. An underwater camera is connected by cable to onshore facilities, which upload images to the Internet via radio signals.

Friday, January 13, 2012

"Fungi which grow Horizontally..."

 John Hill, 1714?-1775. A general natural history: or, New and accurate descriptions of the animals, vegetables, and minerals, of the different parts of the world. . 3 v. London: Printed for Thomas Osborne, 1748-1752. 72[?], plate 4.
Image source.

Wednesday, January 11, 2012

X-ray seahorses


circa 1910: An X-ray photograph of pot bellied seahorses (Hippocampus abdominalis).

From a LIFE gallery of x-rays.

Monday, January 9, 2012

Planktonic protists

The word "plankton" shares a Greek root with "planet" (πλαγκτός, meaning drifting or wandering)-- an etymological link which seems particularly appropriate for these drifting microbes, spherical or stellate in form: 


This beautiful clip is one of a series called Plankton Chronicles, found via The Book of Barely Imagined Beings.

Friday, January 6, 2012

Sponges and their skeletons

Images of sea sponges from the Report on the Hexactinellida collected by H.M.S. Challenger during the Years1873-76; each image shows a sponge framed by examples of the glass-like spines (called spicules) which make up its "skeleton":
Sea cucumbers also have attractive mineralized parts called spicules, but these function as external armor rather than internal support.