Early Argentinan dinosaur discovered


This video is called Paul Sereno talks about Eodromaeus the “Dawn Runner”.

From the University of Chicago in the USA:

New predator ‘dawn runner’ discovered in early dinosaur graveyard

A team of paleontologists and geologists from Argentina and the United States on Jan. 13 announced the discovery of a lanky dinosaur that roamed South America in search of prey as the age of dinosaurs began, approximately 230 million years ago.

Sporting a long neck and tail and weighing only 10 to 15 pounds, the new dinosaur has been named Eodromaeus, the “dawn runner.”

“It really is the earliest look we have at the long line of meat eaters that would ultimately culminate in Tyrannosaurus rex near the end of the dinosaur era,” said Paul Sereno, University of Chicago paleontologist and National Geographic Explorer-in-Residence. “Who could foretell what evolution had in store for the descendants of this pint-sized, fleet-footed predator?”

Sereno and his colleagues describe a near-complete skeleton of the new species, based on the rare discovery of two individuals found side-by-side, in the Jan. 14, 2011 issue of the journal Science. The paper presents a new snapshot of the dawn of the dinosaur era—a key period that has garnered less attention than the dinosaurs’ demise. “It’s more complex than some had supposed,” Sereno said.

Set in picturesque foothills of the Andes, the site of discovery is known as the “Valley of the Moon,” said the report’s lead author, Ricardo Martinez of Argentina’s National University of San Juan. For dinosaur paleontologists, it is like no other.

“Two generations of field work have generated the single best view we have of the birth of the dinosaurs,” Martinez said. “With a hike across the valley, you literally walk over the graveyard of the earliest dinosaurs to a time when they ultimately dominate.”

The area was once a rift valley in the southwest corner of the supercontinent Pangaea. Sediments covered skeletons over a period of five million years, eventually accumulating a thickness of more than 2,000 feet (700 meters).

Volcanoes associated with the nascent Andes Mountains occasionally spewed volcanic ash into the valley, allowing the team to use radioactive elements in the ash layers to determine the age of the sediments.

“Radioisotopes—our clocks in the rocks—not only placed the new species in time, about 230 million years ago, but also gave us perspective on the development of this key valley,” said Paul Renne, director of the Berkeley Geochronology Center in California. “About five million years of time are represented in these layers, from one end to the other.”

In the oldest rocks Eodromaeus lived alongside Eoraptor, a similar-sized, plant-eating dinosaur that Sereno and colleagues discovered in the valley in 1991. Eoraptor’s descendants would eventually include the giant, long-necked sauropods. Eodromaeus, with stabbing canine teeth and sharp-clawed grasping hands, is the pint-sized precursor to later meat-eaters called theropods, and eventually to birds.

“We’re looking at a snapshot of early dinosaur life. Their storied evolutionary careers are just unfolding, but at this point they’re actually quite similar,” Sereno said.

Eodromaeus at the root of the dinosaur family tree

Vexing scientific questions at the dawn of the dinosaur era include what gave them an edge over competitors, and how quickly did they rise to dominance? In Eodromaeus’ day, other kinds of reptiles outnumbered dinosaurs, such as squat lizard-like rhynchosaurs and mammal-like reptiles. The authors logged thousands of fossils unearthed in the valley to find, as Martinez remarked, that “dinosaurs took their sweet time to dominate the scene.”

Their competitors dropped out sequentially over several million years, not at a single horizon in the valley.

In the red cliffs on the far side of the valley, larger plant- and meat-eating dinosaurs had evolved many times the size of Eoraptor and Eodromaeus, but it would be even later when they dominated all land habitats in the succeeding Jurassic and Cretaceous periods.

A New Sauropodomorph Dinosaur from the Early Jurassic of Patagonia and the Origin and Evolution of the Sauropod-type Sacrum: here.

Brief introduction to Patagonian theropods: here.

New Zealand kakapo parrot dies


This is a BBC kakapo video.

From 10,000 Birds blog:

80 year old ‘Richard Henry’, the near-legendary Kakapo which helped ensure the survival of a species once thought extinct, has died. Discovered in 1975 living a bachelor’s life in New Zealand’s fiordland, Richard Henry provided vital genetic diversity when the very last isolated group of this Critically Endangered parrot were found on Stewart Island in the 1980s and taken into captivity for breeding.

While Kakapos are still extremely rare there is little doubt that without the efforts of Richard Henry the species would be in a far more parlous state than it is now. Rest well, old fellow.

See also here.

May 2011. Six of the 11 kakapo chicks hatched on Whenua Hou (Codfish Island) this breeding season have been transferred to a hand rearing facility in Invercargill. Kakapo Recovery programme manager Deidre Vercoe Scott said the healthy chicks would be hand-reared for up to eight weeks, before being returned to Whenua Hou: here.

April 2011. New Zealand has lost an internationally acclaimed conservation pioneer with the death of Don Merton. Don Merton, who was a senior member of the Department of Conservation’s (DOC) scientific staff prior to his retirement in 2005, led the fight to help save both the kākāpō and the black robin from extinction: here.

July 2011. Sirocco the kākāpō is to visit Wellington’s award winning eco-sanctuary: Zealandia. Wellington has never before hosted an adult kākāpō – the world’s rarest parrot. Seeing one is a unique and, until recently, exclusive experienc: here.

Olfactory sensitivity in Kea and Kaka: here.

The numbers of the once-thought extinct, Yellow-eared Parrot have increased to their highest levels since the species was found on the brink of extinction in 1998, when just 81 birds were found in one flock surviving in a remote mountainous area of Colombia: here.

Parrots join apes and Aristotle in the club of reason: here.

The Andes of southern South America form a hostile mountain range with glaciers, salty deserts and meagre high elevation steppes. Birds from more moderate climate zones cross this mountain range only rarely. Nevertheless, many species live on both sides of the Andes, as in the case of the Burrowing Parrot Cyanoliseus patagonus. Researchers from the Max Planck Institute for Ornithology, together with colleagues from the University of Freiburg and the Konrad Lorenz Institute for Ethology, Viena, found that the ancestral population of the Burrowing Parrot occupied what is today Chile, and from there only a single crossing of the Andes was successful: here.

Stewart Island robin: here.

Antarctic biodiversity research


This video is called Destination Unknown South Orkney Islands.

From the Natural Environment Research Council in Britain, with photos:

How biodiverse is a polar archipelago?

It’s a simple question. How many species are there around the South Orkney Islands? David Barnes describes how the answer surprised almost everyone.

For half a century, textbooks have told us biodiversity falls as you move from the tropics to the poles. The idea seemed plausible – after all, how many species can you see on ice-covered land, or ice-scoured shore or shallows?

But nobody seemed to have any evidence for it, or even a good estimate of how many species lived in any particular polar area, except within a few single groups of animals. Even at a time when the International Polar Year and the first World Conference on Marine Biodiversity were approaching, we still didn’t know something as basic as this.

You may be thinking, so what? But there are several very good reasons to understand polar biodiversity. The poles are among the fastest-warming places on the planet, as well as the most vulnerable to ocean acidification, caused by CO2 dissolving in seawater. This is where the planet’s surface is changing most fundamentally – from white to blue.

Polar life may be the most sensitive anywhere to changes in temperature. Experiments have shown polar organisms are least able to cope with short-term warming, perhaps because they have lived for millions of years in an environment whose temperature varies less than anywhere else on Earth. Because of their sensitivity, these organisms can give us information about how life responded to environmental change in the past and so provide an early-warning system for how it will react to what are expected to be the most drastic changes since humans evolved.

Some of this information, such as changes in growth rate, comes from the skeletons of long-lived species. Other insights come from comparison of subfossil and fossil abundances over time and in current species distributions and genetics.

Polar life is clearly very important. So in 2008 a team from the British Antarctic Survey and Hamburg University set about estimating how much of it there is, as well as assessing how good this estimate was.

An isolated archipelago makes the job easier, as it has a definite boundary – the edge of the continental shelf. Confining ourselves to animals larger than a millimetre made it easier still; now all we needed to do was go through thousands of scientific papers, a century of Antarctic expeditions, tens of museums and several international databases, and then mount an expedition to sample across realms, habitats and animal types.

I had spent the early years of my career as a marine biologist continuously working in this archipelago. My boss had spent much of his working life there, and so had his boss. None of us knew what the answer would be – but it would not be 42. On land, in fresh water and on the shore, we quickly built up a picture from the literature; the animals were small and few.

Rich sea, poor land

With 100 species, the South Orkney Islands are rich in land animals compared to elsewhere in the Antarctic, but at the same time poor compared with similar-sized areas in the subantarctic or Arctic, and very poor compared with lower latitude places. Only very young, isolated islands might come close to having so few land species – even a modest garden would have more. Unlike anywhere else, though, just two of these 100 were known to be non-indigenous aliens. This is one of the few terrestrial communities on the planet that remains near its ‘natural’ state.

Lakes and streams were similarly impoverished, with just 65 species. But we found records of 43 known from the shore.

Some of the many marine animals near the South Orkney Islands:

1. A variety of brittlestars [see also here].
2. Sea spiders have more species than anywhere else in the world and are among the animals that grow far larger than their warm-water relatives.
3. Octopus seemed to be particularly common in the study area and were found in most trawls.
4. Feather stars are very mobile – both adults and larvae eat phytoplankton (marine algae) and as such may track the changing patterns of marine algae.
5. Ice fish have no red blood cells and have glycerol in their blood acting as antifreeze.
6. A basket star expanding its curly, branching arms outwards.

Changes in lichen diversity and community structure with fur seal population increase on Signy Island, South Orkney Islands: here.

How do Antarctic notothenioid fishes cope with internal ice? A novel function for antifreeze glycoproteins: here.

Biology of the Antarctic dragonfish Vomeridens infuscipinnis (Notothenioidei: Bathydraconidae): here.

New light on new species? a drill close to reaching 14-million-year-old Antarctic lake: here.

Antarctic crinoids: here.

What International Polar Year discovered: here.

Algae biodiversity cleans streams. The more species a habitat holds, the faster pollutants are removed from the water: here.