Golden jackal
The golden jackal, also called the common jackal, is a wolf-like canid that is native to Eurasia. The golden jackal's coat varies in color from a pale creamy yellow in summer to a dark tawny beige in winter. It is smaller and has shorter legs, a shorter tail, a more elongated torso, a less-prominent forehead, and a narrower and more pointed muzzle than the Arabian wolf. It is listed as Least Concern on the IUCN Red List due to its widespread distribution and high density in areas with plenty of available food and optimum shelter.
Despite its name, the golden jackal is not closely related to the African black-backed jackal or the side-striped jackal, which are part of the genus Lupulella. It is instead closer to wolves and coyotes. The ancestor of the golden jackal is believed to be the extinct Arno river dog that lived in southern Europe. It is described as having been a small, jackal-like canine. Genetic studies indicate that the golden jackal expanded from India around 20,000 years ago, towards the end of the last Last Glacial Maximum. The oldest golden jackal fossil, found at the Ksar Akil rock shelter near Beirut, Lebanon, is 7,600 years old. The oldest golden jackal fossils in Europe were found in Greece and are 7,000 years old. There are six subspecies of the golden jackal. It is capable of producing fertile hybrids with both the gray wolf and the African wolf. Jackal–dog hybrids called Sulimov dogs are in service at the Sheremetyevo Airport near Moscow, where they are deployed by the Russian airline Aeroflot for scent-detection.
The golden jackal is abundant in valleys and beside rivers and their tributaries, canals, lakes, and seashores; however, the species is rare in foothills and low mountains. It is a social species, the basic social unit of which consists of a breeding pair and any young offspring. It is very adaptable, with the ability to exploit food ranging from fruit and insects to small ungulates. It attacks domestic fowl and domestic mammals up to the size of domestic water buffalo calves. Its competitors are the red fox, steppe wolf, jungle cat, Caucasian wildcat, the raccoon in the Caucasus and in Central Asia, and the Asiatic wildcat. It is expanding beyond its native grounds in from Southeast Europe into Central Europe as far as France, and Northeast Europe into areas where there are few or no wolves.
Etymology and naming
The word 'jackal' appeared in the English language around 1600. It derives from the Turkish word çakal, which originates from the Persian word šagāl. The golden jackal is also known as the common jackal.Taxonomy
The biological family Canidae is composed of the South American canids, the fox-like canids, and the wolf-like canids. All species within the wolf-like canids share a similar morphology and possess 78chromosomes, allowing them potentially to interbreed. Within the wolf-like canids is the jackal group, which includes the three jackals: the black-backed jackal, the side-striped jackal, and the golden jackal. These three species are approximately the same size, possess similar dental and skeletal morphology, and are identified from each other primarily by their coat color. They were once thought to have different distributions across Africa with their ranges overlapping in East Africa. Although the jackal group has traditionally been considered as homogenous, genetic studies show that jackals are not monophyletic, and they are only distantly related. The accuracy of the colloquial name "jackal" to describe all jackals is therefore questionable.Mitochondrial DNA passes along the maternal line and can date back thousands of years. Thus, phylogenetic analysis of mDNA sequences within a species provides a history of maternal lineages that can be represented as a phylogenetic tree. A 2005 genetic study of the canids found that the gray wolf and dog are the most closely related on this tree. The next most closely related are the coyote, golden jackal, and Ethiopian wolf, which have all been shown to hybridize with the dog in the wild. The next closest are the dhole and African wild dog, which are not members of genus Canis. These are followed by the black-backed and side-striped jackals, members of the genus Lupulella and the most basal members of this clade.
Results from two recent studies of mDNA from golden jackals indicate that the specimens from Africa are genetically closer to the gray wolf than are the specimens from Eurasia. In 2015 a major DNA study of golden jackals concluded that the six C.aureus subspecies found in Africa should be reclassified under the new species C.anthus, reducing the number of golden jackal subspecies to seven. The phylogenetic tree generated from this study shows the golden jackal diverging from the wolf/coyote lineage 1.9million years ago and the African wolf diverging 1.3million years ago. The study found that the golden jackal and the African wolf shared a very similar skull and body morphology and that this had confused taxonomists into regarding these as one species. The study proposes that the very similar skull and body morphology is due to both species having originated from a larger common ancestor.
Evolution
The Arno river dog is an extinct species of canine that was endemic to Mediterranean Europe during the Early Pleistocene around 1.9million years ago. It is described as a small jackal-like dog and probably the ancestor of modern jackals. Its anatomy and morphology relate it more to the modern golden jackal than to the two African jackal species, the black-backed jackal and the side-striped jackal.The oldest golden jackal fossil was found at the Ksar Akil rock shelter located northeast of Beirut, Lebanon. The fragment of a single tooth is dated approximately 7,600 years ago. The oldest golden jackal fossils found in Europe are from Delphi and Kitsos in Greece and are dated 7,000–6,500 years ago. An unusual fossil of a heel bone found in Azykh Cave, in Nagorno-Karabakh, dates to the Middle Pleistocene and is described as probably belonging to the golden jackal, but its classification is not clear. The fossil is described as being slightly smaller and thinner than the cave lynx, similar to the fox, but too large, and similar to the wolf, but too small. As the golden jackal falls between these two in size, the fossil possibly belongs to a golden jackal. The absence of clearly identified golden jackal fossils in the Caucasus region and Transcaucasia, areas where the species currently resides, indicates that the species is a relatively recent arrival.
A haplotype is a group of genes found in an organism that is inherited from one of its parents. A haplogroup is a group of similar haplotypes that share a single mutation inherited from their common ancestor. The mDNA haplotypes of the golden jackal form two haplogroups: the oldest haplogroup is formed by golden jackals from India, and the other, younger, haplogroup diverging from this includes golden jackals from all of the other regions. Indian golden jackals exhibit the highest genetic diversity, and those from northern and western India are the most basal, which indicates that India was the center from which golden jackals spread. The extant golden jackal lineage commenced expanding its population in India 37,000 years ago. During the Last Glacial Maximum, 25,000 to 18,000 years ago, the warmer regions of India and Southeast Asia provided a refuge from colder surrounding areas. At the end of the Last Glacial Maximum and the beginning of the warming cycles, the golden jackal lineage expanded out of India and into Eurasia to reach the Middle East and Europe.
Outside of India, golden jackals in the Caucasus and Turkey demonstrate the next highest genetic diversity, while those in Europe indicate low genetic diversity, confirming their more recent expansion into Europe. Genetic data indicates that the golden jackals of the Peloponnese Peninsula in Greece and the Dalmatian coast in Croatia may represent two ancient European populations from 6,000 years ago that have survived into modern times.
Jackals were absent from most of Europe until the 19th century, when they started to expand slowly. Jackals were recorded in Hungary with the nearest population known at that time being found in Dalmatia, some 300 kilometers away. This was followed by rapid expansion of jackals towards the end of the 20th century. Golden jackals from both Southeast Europe and the Caucasus are expanding into the Baltic. In the Middle East, golden jackals from Israel have a higher genetic diversity than European jackals. This is thought to be due to Israeli jackals having hybridized with dogs, gray wolves, and African golden wolves, creating a hybrid zone in Israel.
Admixture with other ''Canis'' species
Genetic analysis reveals that mating sometimes occurs between female jackals and gray wolves, producing jackal-wolf hybrids that experts cannot visually distinguish from wolves. Hybridization also occurs between female golden jackals and male dogs, which produces fertile offspring, a jackal–dog hybrid. There was 11–13% of ancient gene flow into the golden jackal from the population that was ancestral to wolves and dogs, and an additional 3% from extant wolf populations. Up to 15% of the Israeli wolf genome is derived from admixture with golden jackals in ancient times.In 2018, whole genome sequencing was used to compare members of the genus Canis. The study supports the African wolf being distinct from the golden jackal, and with the Ethiopian wolf being genetically basal to both. There is evidence of gene flow between African golden wolves, golden jackals, and gray wolves. One African wolf from the Egyptian Sinai Peninsula showed high admixture with the Middle Eastern gray wolves and dogs, highlighting the role of the land bridge between the African and Eurasian continents in canid evolution. There was evidence of gene flow between golden jackals and Middle Eastern wolves, less so with European and Asian wolves, and least with North American wolves. The study proposes that the golden jackal ancestry found in North American wolves may have occurred before the divergence of the Eurasian and North American wolves.