Posts tagged ‘science’

Dinosaur Protofeather Colors

I clearly recall being told in elementary school that the skin colors of dinosaurs are unknown because the necessary parts do not survive the fossilization process. I think that bothered me at first. I got over it eventually and had no trouble accepting that dinosaurs probably were similar in color to some selection of extant reptiles. Still that’s not as nice as knowing for sure.

Let’s put aside dinosaur skin color for now. Scientists have discovered pigments in the protofeathers of some dinosaur fossils. The new observations are of melanin-containing organelles called melanosomes, which exist in the feathers of birds today.

The two most common types of melanin found in modern birds are eumelanin, associated with black and grey feathers, and phaeomelanin, found in reddish brown to yellow feathers.

Both of these types melanin were seen in the fossils being studied.

National Geographic: Dinosaur True Colors Revealed for First Time.

Planetary Society Announces Another Solar Sail Project

I just pulled this one out of my email drafts folder.

Dream of solar sailing in space lives on in new project” discusses an announcement by The Planetary Society to build, launch, and test LightSail-1 — a small craft that will be propelled by solar sail. As explained in the article, previous attempts to launch solar sail craft failed.

I have always been intrigued by the solar sail concept (I am intrigued by a lot of things, though) and will try to keep an eye on this.

Primarily-Vegetarian Spider

I have for a long time been fascinated by the symbiotic relationship between some species of acacias and ants. Honestly, I have also for a long time been fascinated by ants alone. Now some researchers have observed interesting behavior by a species of jumping spider, Bagheera kiplingi, that lives on the same acacia plants.

In many of these ant-plant relationships, the ants are provided food — called Beltian bodies — by the acacia plant. The researchers observed the spider B. kiplingi “hunting” and eating the Beltian bodies as its primary source of food, making this spider the first known to have a primarily vegetarian diet.

Read a summary of the research here. The research manuscript is at doi:10.1016/j.cub.2009.08.049, but you will need an individual or institutional subscription to get the full text.

Ice Memory

I recently read an interested article titled “Ice Memory” in The New Yorker by Elizabeth Kolbert. The article was published in early 2002 and is set in North-central Greenland where, in the summers of 1996 through 2003, scientists drilled an ice core from the top of a glacier down to bedrock at 3085 meters. The ice core encases a climate record back to around 123000 years before present.

The project was called the North Greenland Ice Core Project (NGRIP) and was created to produce an ice core to reproduce (or possibly not) the results obtained from cores extracted by earlier projects, particularly the core produced by the Greenland Ice Core Project (GRIP).

The article covers many topics including recent shifts in the understanding of the climate, a history of Greenland — specifically the first known European settlement of Greenland by the Norse, the objectives of NGRIP, daily life on the ice, and what the ice can tell us.

Central to the article are the startling observations (resulting from the study of earlier ice cores) of extremely abrupt changes in average temperature several times over the last 100000 years. Kolbert writes:

Around fifteen thousand years ago, Greenland abruptly warmed by sixteen degrees in fifty years or less. In one particularly traumatic episode some twelve thousand years ago, the mean temperature in Greenland shot up by fifteen degrees in a single decade.

The story ends considering the relationship between the rise of human civilization and the information extracted from Greenland ice cores.

I have not read enough to know how much agreement there is on the results from Greenland ice cores or what the sticking points are, but in spite of that, the story is quite interesting. More context would, however, be nice.

Since I read this piece more than six years after publication, I wondered what results had come out of the effort, specifically with regards to “Eemian Ice Age Event One”. A paper, “High-resolution record of Northern Hemisphere climate extending into the last interglacial period“, authored by the NGRIP members and published in Nature in 2004, reports that the GRIP ice core that led to the observation of Event One was contaminated by “ice folding”.