Trooper and Sarah: January 2010

Wednesday, January 13, 2010

Wild Iberian horses played part in horse domestication

January 8, 2010

A feral herd of modern Northern Iberian horses. © Carlos Puga

Workers dig at the Portalón archaeological site in the Sierra de Atapuerca (Spain). © Jaime Lira, Centro Mixto UCM-ISCIII

A modern lusitano. © US

Scientists have found evidence that wild horses from Iberia played a part in the domestication of the horse.
The earliest known domestic horses date to 4600 years ago. They originated on the steppes between modern Ukraine and Kazakhstan.

Two different hypotheses have been suggested:

That domestic horses spread from this area over the rest of Eurasia;
That horse domestication was a multiregional process, having occurred several times in different local places.
"Previous analysis on mitochondrial DNA from modern Iberian horses pointed to the D1 haplogroup as the most likely group involved in an independent domestication event, maybe in Iberia or in North Africa" explains Anders Götherström, from the Department of Evolutionary Biology at Uppsala University, who headed the project, together with Juan Luis Arsuaga of the Centro Mixto UCM-ISCIII from Madrid, Spain.
The researchers compared ancient DNA sequences from Iberian horse remains from the Neolithic, Bronze Age and Middle Ages obtained in this study with more than 1000 modern horse sequences from different Iberian and non-Iberian breeds, as well as with ancient sequences from other studies.

The researchers found the earliest occurrence of the D1 group in Iberia in a medieval horse. "We have not found sequences from the Neolithic or the Bronze Age period associated to the most important modern Iberian haplogroup, the D1 group," says Jaime Lira, of the Centro Mixto UCM-ISCIII from Madrid, and the main author of this study.

"That means that D1 group can be a foreigner group, which entered in Iberia during historical times."

The researchers unearthed evidence that wild horses from Iberia contributed to the domestication process, and the Lusitano group C is a witness from this event.

"The Lusitano C is a small group constituted only by modern horses from Iberian origin," explains Arsuaga.

"We have found that maternal lineages from this group were already present in wild Iberian horses from the Early Neolithic, continuing through the Bronze Age until nowadays."

These results suggest the possibility of a completely independent domestication episode, or the use of Iberian maternal lineages in a restocking process from the wild.

Collaborators on the research included scientists from Centro UCM-ISCIII de Investigación sobre Evolución y Comportamiento Humanos in Spain, Universidad Complutense de Madrid in Spain, Stockholm University in Sweden, Universitat Jaume I in Spain, Swedish University of Agricultural Sciences, University of Copenhagen in Denmark and Uppsala University in Sweden.

Ancient DNA reveals traces of Iberian Neolithic and Bronze Age lineages in modern Iberian horses Jaime Lira, Anna Linderholm, Carmen Olaria, Mikael Brandström Durling, M. Thomas P. Gilbert, Hans Ellegren, Eske Willerslev, Kerstin Lidén, Juan Luis Arsuaga and Anders G�therström

Horses can count, new study says

By Nic Fleming, Science Correspondent, 04 Apr 2008

Horses can count, according to a new study that suggests they are more intelligent than previously thought.
Researchers found that, when offered a choice, they consistently choose buckets containing higher numbers of apples.

Babies aged from 10-months-old have been shown to have an innate tendency to opt for containers holding larger numbers of food items, as have many non-human primates such as rhesus macaques and lemurs.   Dr Claudia Uller, of the University of Essex, was inspired to investigate whether horses could count by the story of Clever Hans, a horse that caused a sensation 100 years ago with his apparent abilities to simple arithmetic and keep track of the calendar.
In public performances in Germany he is said to have communicated the answers to questions by tapping his foot.
However psychologist Oskar Pfungst carried out an investigation and reported in 1911 that Clever Hans was not performing arithmetic, but had learnt to obtain the required answers by interpreting the reactions of his maths teacher owner and other observers.
Dr Uller, speaking at the British Psychological Society conference in Dublin yesterday said: "Nobody has been able to show any mathematical abilities in horses since then.
"However our results suggest that horses too, and not only primates, are able to spontaneously discriminate between two small numbers.
"It shows horses are more intelligent than we thought. This may be another piece in the jig saw explaining the evolutionary origins of our ability to count."
Dr Uller and colleague Jennifer Lewis carried out a series of experiments involving riding school and privately owned horses stabled near Colchester, Essex.
In one task, 11 of 13 horses consistently selected buckets containing three plastic apples over another containing two when offered a choice. Fake fruit was used to ensure no difference in smell.
Researchers then showed 12 different horses a box holding either two identical small apples or another containing one large apple with double the surface area. Again, all but two selected the greater number of apples.
In a study published in February, Italian researchers found certain species of fish can count up to four.

Monday, January 11, 2010

Dressage Physiology: Uphill Part 1

In the following articles I will focus on horse physiology to explain form and function of body types in regards to dressage. This will, hopefully, dispel myths about movement and breeds. In these articles I will discuss the basic concepts of classical dressage and discuss myths surrounding the heavy horse or, as some prefer to call them, the draft horse.

There has been much discussion whether a horse should be determined to be uphill by looking at how the (1) seventh cervical vertebrae connects to the spine or should a horse be diagnosed as uphill solely by (2) drawing a line from the top of the withers through to the top of the hip. It should be emphasized that the (3) slope on to the fore has to be considered as well to get the full picture.

Method 1
Connection of the cervical vertebrae to the spine
In the first image of an Arabian horse skeleton, a red line is drawn to show the spine and a purple arrow indicates the seventh cervical vertebrae (the vertebrae that connects the neck to the spine). Notice that with the Arabian skeleton and the Clydesdale skeleton the spine runs strait on to the seventh cervical vertebrae. Now compare the Arabian and Clydesdale to the Thoroughbred. With the Thoroughbred the seventh cervical vertebrae is below the line of the spine. This indicates that the natural build of the Thoroughbred leans forward and places more weight on to the fore. The purpose of the Thoroughbred's lean on to the fore is to place more weight on the front allowing for a more powerful take off while running (see image below).

Other horses who do not have the heavy fore of the thoroughbred will not dip down and dig into the ground during running.

The Spanish horse, in the above image, is shown at the same phase of the stride. In comparison to the Thoroughbred, the Spanish barely dips down. This is a desirable trait in a dressage horse, but not on in a race horse.

When the seventh cervical vertebrae connects straight to the spine the result is a horse with a high stet neck. The high set neck more desirable for dressage horse as it lightens the fore and makes collection easier. Horses with a high set neck are cobs, Spanish horses, Classical horse, Baroque horses, Medieval horses, Heavy horses, Morgans, Saddlebreds etc.