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Researchers studied fossilised remains of a group of Philydrosauras (artist's impression). The semi-aquatic dinosaurs lived 160 million years ago

Many reptiles, such as lizards and turtles abandon their eggs after laying.

In fact, only five per cent of mammals feed and protect their young after giving birth.

But, in a new study, paleontologists have found evidence that dinosaurs may have bucked this lizard trend. 

Fossils reveal that a particular group known as Philydrosauras were caring parents - and it could be the oldest record of such care ever found.

The researchers from the University of Lincoln, along with colleagues from China and Japan, studied fossilised remains of the small semi-aquatic dinosaurs that live around 160 million years ago during the Jurassic Period. 

The fossils, which were found by a farmer in Yixian, in western Liaoning Province of China, four years ago, included an adult surrounded by six smaller juveniles. 

This suggests the dinosaurs were living as a family at the time of their death.   

By comparison, most modern reptiles leave the youngsters to fend for themselves once they hatch.

Dr Charles Deeming, who led the work at the University of Lincoln, said that the young dinosaurs all appeared to be from the same clutch and were living with a parent.

Philydrosauras were part of a group of dinosaurs known as choristodera.

He said: 'The fact that six young surround what appears to be an adult suggests the animals were in natural close proximity at the time of death.

'Although it is possible that the individuals were all swept together during or soon after the event that killed them it is feel that this specimen more likely represents an instance of post-natal parental care.

The fossils included an adult surrounded by six smaller juveniles (illustrated). This suggests the dinosaurs were living as a family at the time of their death. Previous examples of post-natal care in dinosaurs are extremely rare and it has only been reported in two types of dinosaurs, and a small lizard called a pelycosaur

The fossils (pictured) were found in Yixian, western Liaoning Province of China, four years ago. They are said to represent the oldest record of post-natal parental care in diapsids - a group that include all reptiles

'That Philydrosauras shows parental care of the young after hatching suggests protection by the adult, presumably against predators.

'Their relatively small size would have meant that choristoderes were probably exposed to high predation pressure.

'This specimen represents the oldest record of post-natal parental care in diapsids - a group of animals that include all reptiles - to our knowledge and is the latest in an increasingly detailed collection of choristoderes exhibiting different levels of reproduction and parental care.'

Previous examples of post-natal care in dinosaurs are extremely rare and it has only been reported in two types of dinosaurs, and a small lizard called a pelycosaur.

In August, amateur paleontologists found fossils said to be about 120 million years old, in the Lujiatun beds of the Yixian Formation in northeastern China.

The positioning and nature of the fossils shows they all died together, possibly as a result of a landslide caused by a volcanic eruption which would not have given any time for escape. 

But the area was clearly not a nest either, said researchers. 

Though the entire specimen is only about 2ft (0.6m) across, it contains fossils from 25 creatures, all of the species Psittacosaurus lujiatunensis - from the Greek for parrot lizard.

Psittacosaurs were gazelle-like plant eaters and are among the most abundant dinosaurs yet discovered.

This suggests this was a nursery where babies were left in the care of an adult, dubbed 'dinosaur babysitters', said University of Pennsylvania researchers Brandon Hedrick and researcher Professor Peter Dodson. 

Most modern reptiles, such as lizards and turtles, tend to abandon their eggs after laying, leaving the youngsters to fend for themselves once they hatch. A Brazilian Pygmy gecko is pictured

In August, amateur paleontologists found fossils (pictured) said to be about 120 million years old. The positioning and nature of the fossils shows they all died together, but the area was clearly not a nest. Experts believe the area was a 'nursery' where babies were left in the care of an adult, dubbed 'dinosaur babysitters'

The new study, which is published in the Geosciences Journal, was conducted by Dr Deeming along with researchers from the Chinese Academy of Geological Sciences in Beijing and the Hokkaido University, in Japan.

They said that although the group appear to be a family, the sex of the adult is not know.

In some modern species of birds, males play a key role in rearing their young, while in other animals this care is left to the females.

However, the researchers also believe that the small Philydrosaurus dinosaurs may have also given birth to live young rather than laying eggs.

Dr Deeming said: 'Strategies, such as live birth, and post-natal parental care may have improved survival of the offspring.'

'Dinosaur babysitter' fossils were found in the Lujiatun beds of the Yixian Formation in northeastern China