Tuesday, August 30, 2016

2 Fer One - Lightning and Very Lucky People

Everything you always wanted to know about lightning, but didn't know who to ask...

And, a video that may make you believe in guardian angels...


Strange & Esoteric, but Interesting

Geology and Election 2000: Overview

uwgb.edu  23 January 2002, Last Update 11 June 2012
Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay
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On the map of electoral returns for the presidential election of 2000 is a feature instantly recognizable to a geologist: in the otherwise pro-Bush South, an arcuate band of pro-Gore counties sweeps from eastern Mississippi, across Alabama and Georgia and into the Carolinas.

My geologist's eye was immediately drawn to this arc because it coincides almost exactly with a series of rock units on the Geologic Map of the United States. Why would election returns follow rock outcrops?

In the map below, Cretaceous rock units (139-65 million years old) are shown in shades of green. Older rock units are in gray, younger ones in yellow. The complex NE-trending patterns in Alabama, Georgia and South Carolina are deformed rocks of the Appalachians. In NW Alabama, the older rocks are flat-lying layers of the continental interior.

Comparison with the geologic maps shows that the arc actually consists of three segments. 

    In Mississippi and Alabama the pro-Gore band of counties corresponds very closely with the units labeled uK - upper Cretaceous. We might suspect that  the most likely explanation for this part of the arc has to do with economic patterns dictated by the soils. Most of the electoral and demographic patterns associated with the band end abruptly in NE Mississippi.

    In Georgia, the Cretaceous outcrop band is very narrow. It is surprising how clear the pro-Gore band is in Georgia considering how narrow and discontinuous the outcrop band of Cretaceous rocks is. This part of the arc may have less to do with the rocks themselves than the boundary between the Appalachians and the Coastal Plain.

    In South Carolina, however, the band of Democratic counties is well defined but is consistently seaward of the Cretaceous rock units. 

In fact, on some maps there seems to be a weak anti-correlation between the Cretaceous rocks in South Carolina and the political and demographic trends noted for the other three states. However, the South Carolina portion of the arc turns out to be consistent in election returns and a variety of other demographic factors.

This band shows up with varying degrees of prominence for previous elections as well. It shows the same correlation with rock units in Mississippi, Alabama and Georgia and the same lack of correlation in South Carolina. It further shows strong correlation with demographic trends.

The Coastal plain rocks slope gently seaward toward the Gulf and Atlantic coasts, a structure called a homocline. I therefore propose to call the arc of pro-Democratic counties, which is reflected in a variety of demographic trends, the Cretaceous Homoclinal Arc of Demography, which can be abbreviated by an acronym that more than anything else symbolizes the election of 2000: CHAD.


            Given the electoral patterns, the demographic trends of the region are very understandable. There is a pronounced arc of black population. Note that the band follows the Cretaceous rocks from Mississippi to Georgia but, like electoral trends, lies seaward of the band in South Carolina.

            The white population is essentially a mirror image of the black map. 

            And the arc shows up as a diffuse, somewhat broken band of high poverty.

We can now understand why the arc is missing from the 1964 electoral map. 1964 was the last Presidential election before the civil rights reforms of the 1960's took effect, and the lack of any signature on the 1964 map reflects the systematic exclusion of black voters.

Most other demographic data, such as population density, show weak or no correlation with the belt.

Why Geology?

The connection between electoral and demographic patterns we see above is easy to understand. Much less obvious is why they should correlate with a particular set of rock units. The rock units are not particularly rich in resources and differ little from adjacent units. And why is there a continuous band of trends across four states but a geologic correlation in only three of them?

             The arc correlates in part with low elevations.

            The arc also correlates in part with a band of low relief.

However, neither the elevations nor the relief offer any obvious explanation for the political and demographic patterns.

The most obvious candidate for a causative factor is soils and agricultural productivity. Most of the soils of the arc are vertisols, and the soil belt is called the Black Belt or Blackland Prairie in Alabama and Mississippi. The belt has higher than average grass cover, lower than average forest cover, but no dramatically different patterns of crop production or productivity. A recent map of U.S. soil productivity shows above-average soil productivity in this belt.

Land Use and Economics

            A map of agricultural productivity doesn't reveal much. Part of the band is evident in Alabama as a bend of lower than average productivity, but the band has a wide gap in Georgia and is not evident in South Carolina.

            We might suspect a correlation between cotton farming and the Democratic band, and while it is evident, there are other equally important cotton producing areas that were not pro-Gore in 2000.

             Is there a connection between the pro-Gore band and that stereotypical Southern practice, tenant farming? Weak at best. In fact, surprisingly, the prevalence of tenant farming in the South is lower than the national average.

The Past is the Key to the Present

If present-day factors don't clearly explain the band, then they must have origins farther back in history. Let's examine some historical data. We might surmise that the spread of cotton farming and slavery might explain the demographic patterns, so let's start there.

Thanks to Steve Ray for this - you strange man, you.  

Cat Quiz

Can you tell a wild cat from a pet moggy?

It is not going to be as easy as you think. Pit your wits against the ultimate cat trivia challenge

BBC   by Matt Walker 30 August 2016

Cats are cute. That may help explain why so many of us have cats as pets, and perhaps why cats appear to have taken over the internet.

But here at BBC Earth, we want to take you beyond the everyday, and show you the wonderful world as it really is.

There are actually around 37 species of wild cat living today.

Unlike the big cats many people recognise, such as lions and tigers, many wild cat species are small, rare and little-known.

But they are just as deserving of our adoration as the pets we keep at home, and far more endangered.

So to help raise their profile, we thought we would create our own cat challenge.

Can you spot which of the following are wild cat species, and which are breeds of everyday moggy?

The answers, and some tidbits about each tiddles, can be found after the photographs. No early peeking.

Letter a sheet of paper A through P.  Write your answer Wild or Pet next to the letters.

Wild or pet?

Cat A
 Credit: Richard Du Toit/naturepl.com)

Cat B
Credit: Klein & Hubert/naturepl.com

Cat C
Credit: Rod Williams/naturepl.com

Cat D
Credit: Edwin Giesbers/naturepl.com

Cat E
Credit: Mark Taylor/naturepl.com

Cat F
Credit: Naomi Moneypenny/CC by 2.0

Cat G
Credit: Mark Taylor/naturepl.com

Cat H
Credit: Tambako The Jaguar CC by 2.0

Cat I
Credit: Nick Garbutt/naturepl.com

Cat J
Credit: Andy Rouse/naturepl.com

Cat K
Credit: Charlie Marshall/CC by 2.0

Cat L
Credit: Adriano Bacchella/naturepl.com

Cat M
Credit: Edwin Giesbers/naturepl.com

Cat N
Credit: Rod Williams/naturepl.com

Cat O
Credit: Adriano Bacchella/naturepl.com

Cat P
Credit: Madeleine Deaton/CC by 2.0


We started with a difficult felid. This is an African wildcat (Felis silvestris lybica): a subspecies of the wildcat, the species from which domestic cats are descended. Ranging across much of Africa, they look so similar to pet tabby cats that they can be difficult to distinguish in the field. These cats differ from European wildcats, a related subspecies, by their lighter build, less distinct markings, and thin, tapering tails.

Cat B: PET
This furtive feline is a domestic breed, known as the Abyssinian, which has become one of the most popular breeds of short-haired cat in the US. Genetic studies show that domestic cats from both Asia and Europe were used to create the breed, which first originated on the Egyptian coast, not in Abyssinia, Ethiopia as first thought.

It is not getting any easier. This is not your average tabby. This is a black-footed cat (Felis nigripes), Africa's smallest felid, and among the smallest wild cat species in the world. Black-footed cats are found only in three countries of southern Africa: Botswana, Namibia and South Africa. Human activity threatens their numbers. Black-footed cats are solitary, except for females with dependent kittens, and during mating. According to the International Society for Endangered Cats, black-footed cats are incredibly tenacious: native peoples even have a legend claiming these tiny cats can bring down giraffe. While this is untrue, it pays homage to the fierce determination of these feisty little felines.

The ears are a clue, perhaps. This is a very young Eurasian lynx (Lynx lynx), the largest lynx species. It has one of the widest ranges of any wild cat, found from western Europe through the boreal forest of Russia to central and eastern Asia and the Tibetan Plateau. Fewer than 100,000 remain, due to habitat loss, hunting and fur trapping. Larger than most domestic cat breeds, Eurasian lynx can weigh 33-64lb (15-29kg).

Cat E: PET
Another kitten, but this time a pet: a domestic breed known as the Ocicat. Adults are spotted, and though it looks a bit wild, the original Ocicat was created in 1964. It was the unexpected result of an experimental breeding, which attempted to produce an Abypoint Siamese. It was named the Ocicat because of its resemblance to the ocelot, a much larger species of spotted wild cat living in South America.

Cat F: PET
Another domestic breed: the Bengal. Developed to look like exotic jungle cats such as leopards, ocelots, margays and clouded leopards, the Bengal has some wild DNA, having been selectively bred from domestic cats then backcrossed with hybrids of the Asian leopard cat (Prionailurus bengalensis bengalensis). Today, most are descended from other Bengals.

Cat G: PET
If you know your cat breeds, you might expect to see a Maine coon. The largest domesticated cat breed, the Maine coon cat was thought extinct in the 1950s, but it has since been rescued. The origin of the breed is unknown.

This is one a Pallas cat; a Central Asian species (Otocolobus manul), also known as a manul. Looking a little like heavy-set domestic cats, Pallas cats are expressive, and often live at high elevations, up to 16,000ft.

Perhaps more easily recognised as a wild species, due to its long, narrow head and flattened forehead. Accordingly, it is named the flat-headed cat (Prionailurus planiceps). But well done if you guessed the species, as very little is known about it. The flat-headed cat is one of the most threatened cat species in the world, surviving only in Malaysia and Indonesia. It shares a characteristic with the cheetah (Acinonyx jubatus), and fishing cat (Prionailurus viverrinus): its claws are not fully retractile, and can be seen at all times. It also has webbed feet.

This bundle of cuteness is perhaps the hardest to discern. It is a European wildcat kitten (Felis silvestris silvestris), the subspecies related to the African wildcat. They are so similar to tabby cats, even experts can struggle to identify them in the field. The wildcat is the most common and widely-distributed wild cat species in the world. All domestic cats are descendants of a group of wildcats that lived 9,000-10,000 years ago in the Fertile Crescent of western Asia. But the future of wildcats, especially the European subspecies, is threatened: they are increasingly hybridising with feral domestic cats on every continent.

A sand cat (Felis margarita), a close relative of the wildcat (Felis silvestris). As its name suggests it lives across the Sahara, the only cat species to exclusively inhabit desert. Some range into the Middle East and Asia. These cats are renowned diggers, excavating burrows and rodents out of the sand. Their numbers in the wild are unknown, in part because they are rarely seen and their habitat so inhospitable.

Cat L: PET
Renowned for its beauty, this is a domestic cat breed called the Somali. Supposedly alert and intelligent, the Somali is often described as a long-haired Abyssinian. It is descended from Abyssinian cats, and is thought to be a product of a recessive gene in that breed. The picture shows a kitten, going for a bit of a wild walk.

Looking like a burly tabby, this is a wild fishing cat (Prionailurus viverrinus). This species lives in South East Asia, northern India and Sri Lanka. Defying the stereotype that cats do not like water, they are strong swimmers and can cover long distances underwater. They often hunt fish when fully immersed. As wetlands disappear, their population has significantly declined over the past decade.

A Geoffroy's cat (Leopardus geoffroyi): another of the little-known, small spotted cats of the world. Geoffroy's cats range across the pampas grasslands of South America. The fur trade has taken a heavy toll on them, as theirs is the second most commonly sold cat pelt in the international market, after the North American bobcat (Lynx rufus). Significant numbers are also illegally caught and sold into the pet trade, where they are bred with domestic cats to produce exotic hybrids.

Cat O: PET
A domestic breed called the Egyptian mau cat. One of the few naturally spotted breeds of domesticated cat, as can just be seen in the dark image above. They are also reputedly the fastest. A relatively rare breed, the Egyptian mau may be closely related to the Maine coon seen earlier.

We end with what the International Society for Endangered Cats suggests is one of the most beautiful of all wild cats, the Andean cat (Leopardus jacobita). Very little is known about their behaviour or ecology. Only two have ever been weighed by scientists, tipping the scales at around 9lb (4kg). The Andean cat is the most threatened felid in the Americas.

If you got more than half correct, you may curl up and purr a contented purr to yourself.
I missed 2.  C & J