. A thylacine demonstrating the incredible degree to which its jaws can be opened.  It has been suggested that the animal in this photo may possibly be exhibiting a threat display similar to that used by the closely related Tasmanian devil.  This famous image comes from a short film taken by David Fleay at the Hobart Zoo (Domain site) in 1933.

Although the thylacine is not considered to be a particularly fast runner, it is said to have great endurance.  Despite the occasional claims that thylacines work together in hunting packs, E. Guiler states that there is no actual evidence for this.  It has been reported however, that thylacines will lie in wait in a cat-like manner to ambush prey or cautiously stalk it before closing in with a sudden leap.  H. Pearce (a thylacine trapper of the early 20th century) stated that: "A kangaroo was killed by the Tasmanian wolf's standing on it and biting through the short ribs, then tearing open the thoracic cage.".  The thylacine possesses rows of very sharp teeth that have a scissors-like cutting action, and a projecting jaw musculature.  It is capable of opening its mouth very wide.  Some people still maintain that it is able to open its lower jaw to an angle of at least 180º, apparently influenced by old photographs and films which depict the animal yawning.  However, this would be anatomically impossible, since even 90º would result in dislocation of the mandible.  Nonetheless, the thylacine probably has one of the widest gapes achieved by any modern mammal.

   Apart from small mammals, the thylacine's diet probably also includes birds and reptiles.  Upon dissection, the stomach of one thylacine was found to contain the remains of an echidna (Tachyglossus aculeatus).  During the bounty era, sheep ranchers and trappers who hoped to exterminate the thylacine poisoned other animals, since thylacines themselves avoided poisoned baits.  Some people claim that the thylacine prefers organ meats, although Ronald Gunn emphasized that the pair of thylacines which he kept as his residence for a time especially liked to eat the muscles and bones of sheep.  It is interesting that he should make mention of bones, as the thylacine's dentition is not very well suited for dealing with such hard material, unlike its smaller relative the Tasmanian devil.  In zoos, thylacines seemed to readily accept a variety of meats, including horse, goat, kangaroo, rabbit, and even pigeons.  A brief film made of a thylacine at the London Zoo depicts the animal eating in a rather dog-like manner, using its front foot to hold a bone against the ground while tearing meat from it.
 

    A detailed study by E. Crisp in 1855 describes how the intestinal tracts of an adult male were only 6 ft. (1829 mm) in length - approximately half that of a wolf or dog.  Even when one considers that the individual he examined was a small one, with a total length of about 4 ft. (1230 mm), this finding indicates that it is a strict carnivore.  The length of the stomach (when empty), at 8 in. (200 mm) is in view of the body size; the first thylacine ever described (1805) weighed approximately 44 lb. (20 kg).

    A number of thylacine pairs were kept in zoos over the years - including 1902-1905 in Washington, 1902-1904 in Berlin, and six pairs were purchased by the London Zoo between 1850-1891 (1850, 1863, 1884, 1886, 1888 and 1891).  So far as can be deduced from records, captive reproduction is apparently known to have occurred only on a single occasion - at the Melbourne Zoo in 1899 (Paddle 2000).  Although contrary to statements that summer (December to February) is the peak time of breeding, early reports cite that the thylacine's primary breeding season occurs in winter (June to August).
 

. A crouching thylacine which appears to be abnormally lean.  This photo was likely taken at the Hobart Zoo, probably during the 1920s or 1930s.

In a piece of artwork found by Eric Guiler, it can be discerned that a monthly allotment of 152 quite young and half-grown thylacines were delivered for bounty.  According to that, young are produced throughout the year, though there is a marked increase of births in May, July and August.  Because this conflicts with reports which instead regard the thylacine's peak breeding season as summer, the matter is a subject of some debate.  The size of the litter is limited by the four teats.

    The only recorded description of the relationship between mother and young comes from Ronald Gunn:

    "She lies on her side like a dog to suckle her young.  She pulls back the skin of the pouch, thus making access easier to the source of her milk.  If the young are disturbed, they creep with their back downward into the pouch, whereby their mother helps them by lowering the posterior part of her body to help them slip into the pouch.  She positions herself with the posterior part of her body near to the cage wall, thus offering the young some resistance against which to push their hind legs and drive themselves into the pouch."