Scientists find first evidence of dogs traded for Maya ceremonies
Researchers have found the first evidence of live dogs being traded in the Americas - and they were exchanged over distances of more than 100 miles (160km).
The Maya were trading live dogs in 400BC from Ceibal in Guatemala, which is one of the earliest ceremonial sites from the Mesoamerican civilisation, researchers found.
The bones were largely found in the ceremonial centre meaning the animals were probably owned by someone important or could have even been a prestigious gift.
These traded dogs - which were probably slightly bigger than chihuahuas - were older than dogs for eating and were thought to be treated better too.
They would have been used for 'showing off' by elites as something exotic and would have been used in animal and human sacrifices, scientists say.
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The Maya were trading live dogs in 400BC from Ceibal in Guatemala, which is one of the earliest ceremonial sites from the Mesoamerican civilisation, researchers found. Researchers used isotope analysis on bones (pictured) from Maya sites to understand where animals lived and what they ate
Researchers found that animal trade and management began in the Preclassic Period some 2,500 years ago.
Most of the bones and teeth they tested were from the Maya Middle Preclassic period (700-350 BC) and from 400 BC it seems some of these animals were exchanged.
Previously the earliest evidence of live trading dogs was found in the Caribbean in around 1000AD.
'I definitely think dogs were moving before 400 BC, although dog trade probably didn't happen until after people became sedentary and had set settlements to trade between', Ashley Sharpe, an archaeologist at the Smithsonian Tropical Research Institute in Panama who led the research told MailOnline.
'In Asia, Africa and Europe, animal management went hand-in-hand with the development of cities,' she said.
However, in the Americas people may have raised animals for ceremonial purposes.
Researchers believe the dogs had short legs and smaller heads than most medium-sized breeds today.
'Most of the dogs were likely eaten and seem to have died at less than a year old, because their bones are not always fused as they would be as adults', she said.
'The traded dogs might have been treated better, or at least were fully grown.'
Researchers made the discovery by looking at carbon, nitrogen, oxygen and strontium isotopes.
Isotopes are atoms that have the same number of protons and electrons but different numbers of neutrons. This means they have different physical properties.
For example, carbon has two stable isotopes: carbon 12 with six protons and six neutrons and carbon 13 with six protons and seven neutrons.
Researchers analysed animal remains in Ceibal, Guatemala (pictured), a Maya site with one of the longest histories of continuous occupation and one of the earliest ceremonial sites
Most of the bones and teeth they tested were from the Maya Middle Preclassic period (700-350 BC). Dog bones were found at the lowest levels of two pits (pictured), each within a pyramid at the Ceibal, Guatemala site
Carbon in animals' bodies comes from the plant tissues they consume directly or indirectly.
Most plants use the most common type of photosynthesis to turn carbon dioxide into carbohydrates. This process leaves mostly the lighter carbon isotope, carbon 12, behind, bound up in carbohydrate molecules.
Corn, sugar cane and other grasses use another type of photosynthesis that concentrates heavier, carbon 13 molecules.
By looking at these isotopes, researchers could work out what they ate.
The animals fell into two categories - those with lower carbon isotopes were mainly eating wild plants while those with higher isotopes were probably eating corn.
Because people in the region often killed animals that came into gardens and areas where crops were being cultivated, it is possible that peccaries and turkeys may also have been eating crop plants. Researchers found the bones in the Ceibal site
All of the dogs, two northern turkeys, Meleagris gallopavo, the turkey species that was eventually domesticated, and one of two large cats were probably eating corn, which suggests they were domesticated.
Because people in the region often killed animals that came into gardens and areas where crops were being cultivated, it is possible that peccaries and turkeys also ate crop plants.
However, it is likely that turkeys were managed by the end of the Classic Period.
Deer bones showed butcher marks but they were hunted from the forest not domesticated, according to isotope analysis of bones.
One large cat and a smaller cat, probably a margay, Leopardus wiedii, had lower carbon isotopes indicating that they ate animals that fed on wild plants.
The ratio of two strontium isotopes reflects the local geology in a region.
Forty-four of the 46 animals had strontium isotope ratios matching Ceibal and the surrounding southern lowlands region.
Dogs were associated with the deity Xolotl, the god of death. The roundness of this body (pictured) might suggest its value as food for the posthumous soul
Pictured is a Postclassic Maya vessel or incense burner in the form of a dog. Deer bones showed butcher marks but they were hunted from the forest not domesticated, according to isotope analysis of bones that also had lower carbon isotopes
However, to Dr Sharpe's surprise, jaw bones from two dogs excavated from deep pits at the heart of the ancient ceremonial complex had strontium isotope ratios matching drier, mountainous regions near present-day Guatemala City.
'This is the first evidence from the Americas of dogs being moved around the landscape,' Dr Sharpe said.
'The non-local dogs were found in pyramids at the centre of the site, so they may have belonged to someone important who came from far away, or were gifts', Dr Sharpe said.
'We have no clear evidence they were sacrificed, but perhaps they were valued as "shown off" purposes by the early elites as something exotic and special.'
Part of the jaw bone and teeth of a big cat was found with one of the dogs in the same deposit.
'The interesting thing is that this big cat was local, but possibly not wild,' Dr Sharpe said.
'Based on its tooth enamel, it had been eating a diet similar to that of the dogs since it was very young.'
Researchers have not yet worked out if it was a jaguar or a puma. It was captured and raised in captivity, and may have lived near villages and eaten animals that were feeding on corn.
'It's interesting to consider whether humans may have had a greater impact managing and manipulating animal species in ancient Mesoamerica than has been believed,' Dr Sharpe said.
'Studies like this one are beginning to show that animals played a key role in ceremonies and demonstrations of power, which perhaps drove animal-rearing and trade.'