Daily Archives: December 6, 2021

‘Not in my backyard’: The thorny issue of storing German nuclear waste • FRANCE 24 English

FRANCE 24 English

Dec 6, 2021

#Germany is to shut down its last #nuclear reactors next year. However, the country still has no place to store the 27,000 cubic metres of highly radioactive material it has already produced, with the amount set to grow as power stations are decommissioned and dismantled. German authorities have set a deadline of 2031 to find a permanent storage location – but for now, the waste is being stored in temporary locations, much to the anger of local residents. Our correspondents report.

Fish species in Lake Tana genetically surprisingly similar

The different species of barbels in Lake Tana in northern Ethiopia have evolved from a common ancestor. When biologists from Wageningen University first described the fifteen species over twenty years ago, it was not yet possible to examine the precise genetic differences between these carp species. Now, together with a colleague from Portugal, they have mapped the genetic basis of the diversity. Their work has been published in the Journal of Fish Biology.

Lake Tana was formed by volcanic damming of the Blue Nile. The ancestral species that lived in the river, has probably diverged into at least fifteen different species within the lake. This species flock can only have originated after the last ice age, because then the lake was completely dried up and only the Blue Nile itself and some small rivers contained water. That means that the speciation took place in no more than 13 thousand years: extremely fast for evolutionary developments. The species differ greatly in size (adult animals vary from less than 20 centimetres to about one meter), in form (with long narrow bodies and large mouths, but also with flattened bodies and small mouths), in their diet (ranging from plants to snails and even other fish) and in their reproductive behaviour (in different parts of small rivers that enter the lake or in the lake itself). At that time it was not possible to investigate the genetic basis of this diversity in detail, due to technical constraints.

Closely related

By using modern DNA techniques, the genetics of the Tana barbels have been partly clarified. Throughout the whole lake tissue samples have been collected systematically. These have been analysed by a collaboration of researchers from Wageningen from Aquaculture and Fisheries, Experimental Zoology, the Animal Breeding and Genomics Centre and IMARES, together with the Centre of Marine Sciences in Portugal. This analysis shows that the total genetic variation is very limited, which was also determined for the famous cichlids in Lake Victoria.

Barbels that differ greatly in appearance and consume different kinds of food are genetically most distinct. This supports the scenario that the speciation has occurred in Lake Tana due to the various species of fish each specializing into their own ecological niche.

Field work essential

The study shows that it is not easy to determine whether fish belong to different species on genetic grounds alone. The study of other characteristics, such as appearance and ecology, but also behaviour in their natural habitat, thus remains essential.

More information: L. A. J. Nagelkerke et al. “Shallow genetic divergence and species delineations in the endemic species flock of Lake Tana, Ethiopia,” Journal of Fish Biology (2015). DOI: 10.1111/jfb.12779

Journal information: Journal of Fish Biology

[Excerpt from:] GLAM CMS Holiday Cocoa 2021-12-04

 [This is a brief overview of digital research with maps and views of Africa during the slave trade era.  It is excerpted from the Zoom recording of the “member’s sharing” session of GLAM CMS – The California Map Society – on 4 December 2021. To view the excerpted segment tap on the red YouTube arrow below:]

California Map Society Dec 5, 2021


[Detail of image and map of Cape Coast Castle, Ghana from an
18th century print, excerpted from the California Map Society online member’s meeting, 4 December 2021.] 

See related:


The Declining U.S. Birthrate Comes As No Surprise

6 Dec 2021
There are a lot of headlines detailing a drop in birth rates, but has anyone wondered why? MSNCB’s host of American Voices, Alicia Menendez, details how the state of our country is impacting those statistics.

Dakar peace forum: Talks set to spark dialogue on Africa’s post-Covid future • FRANCE 24 English

6 Dec 2021
After six editions, the #Dakar International #Peace and Security Forum will take place in a singular context as the #Covid-19 #pandemic continues. FRANCE 24’s Marc Perelman tells us more.

BBC World Service – Newshour, Scientists say Omicron virus spreading twice as fast than Delta

Researchers say Omicron appears to be spreading twice as fast as the Delta variant.

BBC World Service – Newshour, Pope Francis has denounced those who use migrants for political propaganda

The Pope made his remarks on a visit to the Mavrovouni refugee camp on the Greek island of Lesbos.

Green Revolution Causing Africa’s Land Use Problem

“The Elephant” in Kenya published my article on the failure of Africa’s Green Revolution to achieve “sustainable intensification” – growing more food on the same land through productivity increases. Rather, the data show that incentives for corn, rice and a few other crops are promoting “unsustainable extensification” – the potentially damaging expansion of agriculture onto new lands. Far from being a solution to unsustainable land use, Africa’s Green Revolution is a principal cause.

It is a myth that the only way to increase productivity on existing agricultural lands is through Green Revolution programmes and evidence shows that they are among the principal causes of unsustainable land use.

By all accounts, food and agriculture were barely on the agenda at last month’s U.N. Climate Summit in Glasgow, Scotland. They should have been. Food production, distribution, consumption, and waste contribute an estimated one-third of greenhouse gas emissions. In production the majority comes from unsustainable livestock production with another large share coming from the production and use of synthetic fertilizers. But a significant share also comes from “land-use change,” a neutral term for the destructive expansion of agriculture onto new land.

That sort of “extensification” of agriculture can have serious environmental consequences – deforestation, soil erosion, unsustainable water use, etc. Those in turn have important implications for climate change, as a recent U.N. report highlighted. Land-use changes due to agricultural expansion increase carbon emissions from land clearing, eliminate carbon-dioxide-absorbing plants such as rainforests, and create greenhouse gases with modern farming methods. According to the U.N., they account for about 30% of agriculture-related emissions.

A simplistic neo-Malthusian perspective attributes extensification to growing populations exerting pressure on scarce natural resources. Increasing farmers’ productivity on existing lands in regions such as Africa where yields are relatively low is the mainstream solution. The goal is to foster “sustainable intensification” – growing more food on the same land. With commercial inputs such as commercial seeds and synthetic fertilizers, farmers can intensify their exploitation of existing agricultural land, raising productivity and easing pressures from growing populations to bring new lands into cultivation.

…(read more).

Read the full article at The Elephant….