Chinese fossil fish discovery


This video is called Evolution fish with fingers. Transitional fossils.

From PLoS ONE:

Fossil Fishes from China Provide First Evidence of Dermal Pelvic Girdles in Osteichthyans

Abstract

Background

The pectoral and pelvic girdles support paired fins and limbs, and have transformed significantly in the diversification of gnathostomes or jawed vertebrates (including osteichthyans, chondrichthyans, acanthodians and placoderms). For instance, changes in the pectoral and pelvic girdles accompanied the transition of fins to limbs as some osteichthyans (a clade that contains the vast majority of vertebrates – bony fishes and tetrapods) ventured from aquatic to terrestrial environments.

The fossil record shows that the pectoral girdles of early osteichthyans (e.g., Lophosteus, Andreolepis, Psarolepis and Guiyu) retained part of the primitive gnathostome pectoral girdle condition with spines and/or other dermal components. However, very little is known about the condition of the pelvic girdle in the earliest osteichthyans. Living osteichthyans, like chondrichthyans (cartilaginous fishes), have exclusively endoskeletal pelvic girdles, while dermal pelvic girdle components (plates and/or spines) have so far been found only in some extinct placoderms and acanthodians. Consequently, whether the pectoral and pelvic girdles are primitively similar in osteichthyans cannot be adequately evaluated, and phylogeny-based inferences regarding the primitive pelvic girdle condition in osteichthyans cannot be tested against available fossil evidence.

Methodology/Principal Findings

Here we report the first discovery of spine-bearing dermal pelvic girdles in early osteichthyans, based on a new articulated specimen of Guiyu oneiros from the Late Ludlow (Silurian) Kuanti Formation, Yunnan, as well as a re-examination of the previously described holotype. We also describe disarticulated pelvic girdles of Psarolepis romeri from the Lochkovian (Early Devonian) Xitun Formation, Yunnan, which resemble the previously reported pectoral girdles in having integrated dermal and endoskeletal components with polybasal fin articulation.

Conclusions/Significance

The new findings reveal hitherto unknown similarity in pectoral and pelvic girdles among early osteichthyans, and provide critical information for studying the evolution of pelvic girdles in osteichthyans and other gnathostomes.

Antarctic warming damages Adélie, chinstrap penguins


This video is called Adelie penguin and chick on Torgersen Island.

From Wildlife Extra:

Antarctic warming changing penguin breeding cycles, and success

Gentoo happier than Adelie & Chinstrap

March 2012. Three penguin species that share the Western Antarctic Peninsula for breeding grounds have been affected in different ways by the higher temperatures brought on by global warming, according to Stony Brook University Ecology and Evolution Assistant Professor Heather Lynch and colleagues.

Lynch and her colleagues used a combination of field work and, increasingly, satellite imagery to track colonies of three penguin species – Adélie, chinstrap and gentoo. The Adélie and chinstrap migrate to the peninsula to breed, while the gentoo are year-round residents.

Rapid warming

The Antarctic is considered one of the world’s most rapidly warming regions. Warmer temperatures move up the breeding cycle, causing the penguins to lay their eggs earlier. The resident gentoo population is able to adapt more quickly and advance their “clutch initiation” by almost twice as much as the other species. Lynch believes this may allow them to better compete for the best nesting space. The Adélie and chinstrap are unaware of the local conditions until they arrive to breed and have not been able to advance their breeding cycles as rapidly.

Gentoo numbers booming, Chinstrap and Adelie declining

In addition, the gentoo prefer areas with less sea ice, and have been able to migrate further south into the Antarctic as the sea ice shrinks. The chinstrap and Adélie species rely more heavily on the abundance of Antarctic krill, which require sea ice for their lifecycle.

The result – the gentoo numbers are increasing while the other two species have noticeably dwindling populations on the Antarctic Peninsula.

The work by Lynch and her team is contained in three papers that have been published online in Polar Biology, Ecology and Marine Ecology Progress Series (MEPS).

See also here. And here.

I had the privilege of seeing all those three penguin species in the Antarctic decades ago. It is heartbreaking that Big Oil and their accomplices ruin the Antarctic this way now.

Global Warming Brings More Lyme Disease, Ticks: here.

Now You Sea It, Now You Don’t: Watch Arctic Sea Ice Melt: here.

Dutch mallard nest webcam


This video from Bakkerswaal nature reserve in the Netherlands is about catching ducks in the traditional way. Those ducks are then ringed, and released, helping to get more information about bird migration etc.

There is a webcam right now of a mallard nest in Bakkerswaal nature reserve in the Netherlands.

Traditional duck catching on Vlieland: here.

Saving young mallards on Vlieland island: here.

Ibiza lizards evolution video


This video says about itself:

Battle of the Sexes

by Day’s Edge Productions

WINNER of the 2011 Animal Behavior Society Film Festival (Non-commercial division).

A short film about Nate Dappen’s research on how males and females coevolve together. Nate is working on his PhD in evolutionary biology at the University of Miami, Florida. He studies sexual coevolution and color evolution in the Ibiza wall lizard (Podarcis pityusensis).

Film by: Nate Dappen & Neil Losin. Additional photography by Joris van Alphen. Narrated by John Astbury. See credits for music.

To learn more, visit daysedgeproductions.com/

See also here.

Lichens might survive on Mars


This video is about lichens.

Translated from Griet Nijs’ Dutch in Belgium:

Life on Mars after all?

Message from Natuurpunt Study (Belgium) on Tuesday, April 3, 2012

For many years, science has been asking itself whether there is life on Mars. In an attempt to finally get out of this impasse, researchers have exposed several lichens to space conditions and have monitored whether they survived. The results are at least surprising.

Research into life on Mars is not new. During the last twenty years, it has been proved several times that prokaryotes, cells without nuclei such as bacteria, can survive under simulated or real space conditions. They can survive a high dose of UV radiation, extreme temperatures and even vacuums. Some prokaryotes would even survive the extreme conditions on Mars.

Over the past decade there were also the first experiments with eukaryotes, organisms with a more developed cell structure, including humans, animals and plants. Lichens also belong to the eukaryotes. Lichens are essentially a symbiosis (a form of society with mutual benefit) between a fungus and a green alga or cyanobacteria. The mold retains water and provides protection while the algae take care of the production of sugars through photosynthesis.

When scientists exposed some lichens, such as Xanthoria elegans, a lichen also of alpine and polar regions, and Fulgensia bracteata, to conditions like in space, they were found to have high resistance against this. When the algal symbionts were separated and therefore could not benefit from protection by the fungus, they lost their capacity for growth. The physiological capacities were reduced to 42%. This suggests that the symbiosis between the fungus and the algae increases the ability of both partners to survive under space conditions.

Based on the results of the simulated space conditions, Xanthoria elegans, Aspicilia fruticulosa and Rhizocarpon geographicum were then subjected to a real space test. It showed that after ten days in space, only a minimal effect occurred. An exposure of eighteen months in space brought more effects. While A. fruticulosa and Xanthoria elegans still showed photosynthesis and physiological activity, it turned out that Rhizocarpon geographicum was slightly damaged.

These results inspired the researchers to go one step further. They decided to expose Xanthoria elegans to a range of parameters such as those found on Mars. The atmosphere, extreme temperatures, humidity, UV radiation and available minerals were simulated. Xanthoria elegans, which also occurs here in Flanders, showed an exceptional survival capacity when it was exposed to these conditions for four days. From these results one can deduce that eukaryotic symbionts may be able to survive in regions of Mars where liquid water is present.

The results of this study show that not only the most primitive life forms could survive on the surface of planets in our solar system. We do not know if they have reached those planets. But life as we know it would therefore be possible on other planets …

Source: de Vera JP, Lichens as survivors in space and on Mars, Fungal Ecology (2012), doi: 10.1016/j.funeco.2012.01.008

Lichen Can Survive in Space: Space Station Research Sheds Light On Origin of Life; Potential for Better Sunscreens: here.

Lichens of Dutch Ameland island: here.

Algal blooms can cause serious – even fatal – problems in our waterways, but scientists know little about what causes them: here.

North American warbler video


This video from the USA says about itself:

Big Day Warbler Warm-up Quiz

2 April 2012

To help you make the most of your spring birding give this “Warbler Warm-Up” a try. And please pledge to help Team Sapsucker as they attempt to break the North American Big Day record by finding the most bird species in 24 hours.

See here.

Yellow-bellied sapsucker: here.