Zebra stripes and leopard spots

Linkhttp://www.sherborne.org/, http://www.turing.org.uk/turing/, http://www.livescience.com/, http://www.uap.ualberta.ca/

One of my favourite pastimes is storytelling. When we visit my granddaughters one of the first stories they ask for is How The Zebra Got His Stripes and here is a condensed (very condensed) version.

A long time ago, when zebra was pure white, a brave young zebra decide the challenge baboon for access to water, which the latter had claimed for his own. After a long and terrible fight baboon began to get the upper hand and pushed zebra into a fire. The pain was so severe that the zebra jumped up and lashed out, kicking the baboon clear across the river where he landed on some rocks. The upshot, the zebra was scarred for all time, but the baboon ended up with a bare backside after damaging itself upon landing.

It is no surprise that folklore about other animals, particularly leopards and serval cats, tell how they got their markings after ending up involved with fire. Here are a couple of pictures that you might enjoy. The smaller serval cat was a bottle-raised animal that lived in Kenya's Meru National Park around the home of chief Warden Peter Jenkins and his family in the late 1960s. I have stories about Peter in both of my books.

Another fun component of storytelling is trying to find ways of linking these ancient and entertaining interpretations of the things that people saw around them to modern scientific explanations of how things work and for me it has always been a challenge to do that with these “burn” stories.

Like the mythical American cavalry of the old Hollywood Westerns, or the more modern arrival of the marines (satirized so brilliantly by Tom Lehrer) science has come to the rescue.

In a posting of April 7th headlined Study Reveals How Creatures Get Spots vs. Stripes
LiveScience managing editor Jeanna Bryner takes us into recent information about fruit flies and their markings, and links us back to her own older post about leopards and their spots.

“Biologists have long wondered how leopards and other mammals acquired their distinct and uniform coat patterns. In 1952, British mathematician Alan Turing developed an equation to explain how simple chemical reactions produce the spots, stripes, and swirls that decorate a variety of mammals.”

By a strange coincidence I have a weak link with Turing, as he was at the same school as me (although of an earlier generation). He has been dubbed by many in the field "the father of modern computing" and is known to have had a huge influence upon the ENIGMA machine that let the Allies break to German codes of WWII. Here is a photo of Turing that I found on line. I could have chosen any one of hundreds, as a Google search for them got me to 49 pages. A second family link to Turing ties in with the fact that my daughter is heavily involved with computing, artificial intelligence and the world of robots. For the folks in her world Turing is an icon.

Anyway, back to leopards, zebras and the spot/stripe question.

Turing's mathematical model could not account for the evolution of markings as the leopard matures from spotted cub to rosette-dappled adult.

As a Bryner relates a team of scientists from Taiwan’s National Chung-Hsing University in Taichung and England’s Oxford University “modified Turing's model and ran it through computers, concluding that substances called “morphogens”, chemicals secreted by pigment cells in the coat, diffused through the coat and led to the development of the distinctive patterns seen in adults.”

A really positive clue came from more recent work with a species of fruit fly, which are much easier, cheaper and safer to study than big cats. In this case the wing spots, which are the natural pattern, were converted into stripes by means of gene manipulation and understanding of the location of the morphogen-linked gene. "We can make custom flies," said Sean Carroll, a molecular biologist at the University of Wisconsin-Madison, and the senior author of the report published this week in Nature and referred to by Bryner.

Of course none of this explains the weird story of the quagga, an almost mythical beast that actually existed in the most southern regions of South Africa and was exterminated in the late 1800s. The quagga was a form of zebra that only had stripes on the front half of its body, the rear half being self-coloured. The last known one died in an Amsterdam zoo in 1883.

When I was in South Africa in the early 90s there were several groups exploring the possibility of doing a sort of Jurassic Park experiment to try and re-create the quagga from DNA in old hides. I later heard that they had abandoned the effort when they discovered that it was just a type of zebra.

In another LiveScience posting titled How A Zebra Lost Its Stripes an analysis by a team of German and US scientists show that the quagga diverged from plains zebra in Africa during the last Ice Age. It then developed the colour markings that made it look as if it might have come from a Dr. Doolittle story.

Or maybe it was another white zebra that got into a fight with a baboon but only got burnt on the front half of its body. It's just a question of what you choose to believe.

R & R in Murchison Falls NP

Students away safely on Friday evening and due for some R&R in Amsterdam. Hope we did not work them too hard. I don’t think so & I received a moving and kindly though-of book of paragraphs written by each one of them saying how the experience had affected them. Not for sharing here, but something for me & Jo to treasure.

As they were landing in Holland Jo, Geraldine (her sister) and I headed out on a week’s R&R of our own. Our vehicle was a Land Cruiser belonging to my colleague Dr. JB Nizeyi and driven by professional driver/guide Dauda, which took all the pressure off us, me especially, as I have no driving to do for a whole week.

Our first stop was Murchison Falls NP, and this where we spent 2 nights, saw many species that we had not seen on other parks, had a great ride on the Nile in the tour boat, and enjoyed the rest.

Highlights included close-encounters with pair of Abyssinian Ground Hornbills, shown here, with the male having both red & blue bare skin over cere and neck, the female only blue. These turkey-sized birds are almost never seen flying, but stalk purposefully through the grass looking for food over large home ranges.

We also saw lots of Uganda kob, Rothschild’s giraffe, buffalo, warthogs and hundred’s if not thousands of Abdim’s storks, which were scattered everywhere, also foraging when not circling on the thermals. I almost forgot to mention two other mammals, one common, one less so. Oribi, a dainty antelope with a distinctive black spot behind the eye, are the common ones. Leopard the others. Our most unusual sighting was of a very close association between these two when the cat crossed the track in front of us carrying a partly devoured example of the antelope.

As we circled on one of the many tracks we came across this old bull elephant having a good scratch against the trunk of a Bourassas palm. It must have felt good!

Anthrax from drums

There’s a horrible story from Scotland about a drummer who died of anthrax in 2006. The inquest determined that he got the disease after inhaling spores. It seems as if he was exposed at a drumming class in at Smailholm village hall near Kelso in the Scottish borders.

The report reached me through the important source of Promed-ahead the very detailed Listserv that covers the entire gamut of infectious diseases of all living things, from plants to humans. You can visit ProMED-mail's web site here to learn more about this superb service, which is available to anyone and everyone, and is only supported through private funds, with no government involvement. This ensures that it remains truly independent.

Anthrax seems to be reported at least once a month, sometimes once a week, from somewhere in the world and it was a serious problem three years ago in Queen Elizabeth National park, Uganda, when a large number of hippo died. The year before the outbreak it was common to see leopard on the channel track near Mweya Lodge, but they all disappeared and the next year we saw none. It is a reasonable assumption that they fed on carcasses and died of this disease. We saw this hippo in the park’s Lake Edward the year before the anthrax outbreak, and one of our MSc students, Dr. Eddie Kambale of the DRC went out to take a swab form an open wound on its neck. It was anthrax negative, and we saw other wounds. The likelihood is that it died in a fight.

There does not seem to be any information on the source of the drums and whether they originated in the UK, or came in from overseas. With the frequent reports of this nasty disease from so many corners of the world I just hope that the drums these kids are playing with at the Kasenyi Primary School in QEP were not from anthrax carcasses. It would seem not, as the drums have been at the school for 4 years and are frequently played.

Source: The story ran in (promed-ahead-digest-Owner@promed.isid.harvard.edu ProMED-AHEAD Digest of Friday, November 28 2008 (Volume 2008 : Number 304)

Gorillas, Conservation and Trouble in Paradise

One of the very best sources of news about conservation and wildlife issues cannot be considered a mainstream source of such information, but it is very much a mainstream source of world news. It is the BBC news web site that you can find here.

Within the site it is easy to navigate to almost anywhere in the world, and two recent reports caught my eye.

The first is a well-edited film clip, is titled Turmoil Troubles Masai Reserve and its subheading reads “Kenya's tourism slump after the recent political violence is threatening the Masai Mara game reserve.” You can find the footage here.

It opens with a shot of a small group of elephants walking across the grassy plain but quickly shifts to an interview with a Maasai community leader who tells of his struggles to look after his family in the face of collapsing tourist industry income. The original post was made in March this year, and I do not have the most recent information about any recovery. Maybe a reader has more to tell us. Let’s hope it is less pessimistic than the clip.



My own shots from the Mara bring back happy memories of several visits.

The second BBC item can be found by going directly to at this URL, or accessed through the gorilla wildlifedirect spot of the blog here about the desperately difficult situation in the Democratic Republic of the Congo and the park rangers who try to protect the Virunga area. They concentrate on two closely related things, gorillas and charcoal.

It is headed Diary: Protecting Mountain Gorillas and the sub reads “Two rangers share their experiences of protecting mountain gorillas in Virunga National Park, DR Congo".

The most recent post on the direct blog tells of a horror story in a troubled land. The heading reads Ranger Shot 12 Times and Killed in Virunga by Rebels. Over to you.

On the lighter side, for a bit of what she titles “Tee hee hee” humour about my own blog series you can go to writer, director, actor and television host (not to mention award winner) Nicole Stamp’s blog.