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[top] Thin-section transmission electron micrograph (TEM)

This TEM reveals the ultrastructural appearance of a single virus particle, or “virion”, of measles virus. The measles virus is a paramyxovirus, of the genus Morbillivirus. It is 100-200 nm in diameter, with a core of single-stranded RNA, and is closely related to the rinderpest and canine distemper viruses.   [Source]

[bottom]  Image: Pasieka/Science Photo Library 
               Via New Scientist

Latest Paleo illustration from Nobu Tamura:
Astraspids: Jawless armored fish from the Ordovician 
455 million years ago

Source: Nobu Tamura / Spinops

Astraspis (‘star shield’) is an extinct genus of primitive jawless fish from the Ordovician of Central North America and Bolivia (Astraspis - Wikipedia)

Astraspis desiderata Walcott, 1892
Chordata → Craniata → Agnatha → Pteraspidimorpha → Astraspida

Late Ordovician  //  Harding Fm  //  Colorado, US
Length: 20 cm

The headshield of Astraspis was made of hundreds of small bony plates called tesserae. With Eriptychius, they constitute the earliest known definite vertebrates from North America. 

April 20, 2014 // Copyright © Nobu Tamura under Creative Commons 3.0 Unported 

More information at Tamura’s Paleo Exhibit …

A cascade of failing ecosystems

Review Article: Trophic Downgrading of Planet Earth
James A. Estes, John Terborgh, et al.

"Modern extinctions are largely being caused by a single species, Homo sapiens. From its onset in the late Pleistocene, [this] sixth mass extinction has been characterized by the loss of larger-bodied animals in general and of apex consumers in particular."

  • [1] “The loss of apex consumers is arguably humankind’s most pervasive influence on the natural world. This is true in part because it has occurred globally and in part because extinctions are by their very nature perpetual, whereas most other environmental impacts are potentially reversible on decadal to millenial time scales.”
  • [2] “The omnipresence of top-down control in ecosystems is not widely appreciated because several of its key components are difficult to observe. The main reason for this is that species interactions, which are invisible under static or equilibrial conditions, must be perturbed if one is to witness and describe them. Even with such perturbations, responses to the loss or addition of a species may require years or decades to become evident.” 
  • [3] “Recent research suggests that the disappearance of these animals reverberates further than previously anticipated, with far-reaching effects on processes as diverse as the dynamics of disease; fire; carbon sequestration; invasive species; and biogeochemical exchanges among Earth’s soil, water, and atmosphere.”

Science 15 July 2011: Vol. 333 no. 6040 pp. 301-306 

Actual implementation of any of the IPCC recommendations
looks like it’s going to depend on self-interest (enlightened or otherwise).
How’s that working for us so far? I wonder …

From the World Nuclear Association blog:

The conclusions of the full IPCC report are clear, the energy supply system is the largest contributor to global greenhouse gas emissions and more action in this sector is required now.

The IPCC report says around 80% of our electricity must be supplied by low carbon sources such as nuclear, renewables and CCS by 2050 and to eliminate polluting coal, oil and gas generation by the end of the century.

The IPCC concludes that no single mitigation option in the energy supply sector will be sufficient to hold the increase in global average temperature change below 2°C above pre‐industrial levels. Embracing all options will give us the greatest chance of avoiding the harmful effects of climate change in the most cost-effective way.

SOURCE:  World Nuclear Association

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