Family values: were dinosaurs the first social creatures?

The majority of dinosaurs were peaceful, plant-eating creatures that developed the Earth's first strong social communities.

Herds, packs and families of dinosaurs were commonplace. Many fossils have been found where groups of dinosaurs died together, such as the ones which sank in the quicksand off the Isle of Wight. In Alberta, Canada, a mass grave has been discovered containing at least 300 grazing dinosaurs of all ages and sizes. This herd was swept to death by a flash flood while trying to cross a deep river. In Montana, in the USA, an even bigger herd of about 10,000 dinosaurs has been discovered. These creatures were poisoned by volcanic gases and buried in ash. Their fossilised bones stretch out in a straight line for more than a mile.

Modern understanding of how dinosaurs lived together was transformed by a fossil specialist called Dr Jack Horner, who made a most extraordinary discovery in the mid-1970s. Horner and his team were fossil-hunting in Montana when they came across America's first dinosaur nesting site. They found a number of dinosaur eggs as well as the fossilised remains of baby dinosaur embryos. They called these creatures Maiasaura, which means "good mother lizard". Each season Maiasaura returned to the same breeding grounds where they refurbished their old nests. These dinosaurs lived in colonies and looked after their young in herds until they were old enough to start families of their own. Here, beyond all reasonable doubt, lie the origins of the family unit. More than 200 dinosaur-egg sites have now been found across the world. The eggs range in size from as small as a pebble to as big as a football.

Other dinosaur-like creatures, too numerous to mention, also lived through these times. The pterosaurs were enormous flying reptiles that dominated the prehistoric skies. One of them holds the world record for biggest wingspan of any creature ever to have lived. At nearly 20m across, its wings were as large as those of a Second World War Spitfire.

A mystery of feathered flight: where did the world's first birds come from?

Hermann von Meyer, a German fossil-hunter, thought he'd got the answer to this puzzle in 1861 when he announced the discovery of what he claimed was the first ever bird. He called it Archaeopteryx. It was about the same size as a modern magpie, and was definitely bird-like. Its feathers were arranged in just the same way as modern birds', with an aerodynamic configuration to make flight possible. It even had bird-like claws on its legs, and a wishbone.

Von Meyer's fossil dated back some 140 million years, at about the same time that the first flowers were beginning to bloom ( see Part 2). Since then, a further 10 Archaeopteryx specimens have been found in a region of Germany called Solnhofen. But for years a mystery remained. From what did these creatures descend, and how did they learn to fly? So perplexing was this puzzle that the birds were shunted into their own separate group, neither reptiles like the dinosaurs, or mammals like man. They were just, well, birds.

Then, in 1995, Chinese scientists announced that they had dug out a fossil which proved conclusively that some dinosaurs did indeed have down-like feathers. Sinosauropteryx caused a sensation. It was a small, 1.5m-long, two-legged dinosaur with the jaws and flattened teeth typical of meat-eating dinosaurs. It had clawed fingers, and its hind limbs show that it must have been a fast runner. At last, the puzzle of where birds descended from seemed to have been solved. They are indeed the last and only surviving branch of the dinosaurs. But this still left several perplexing questions unanswered.

Sinosauropteryx feathers show no signs of the aerodynamics needed for lifting a body into the air. It couldn't fly. So what were its feathers for? Experts began to think that perhaps feathers were not originally intended as equipment for flight at all. Perhaps it was only later, by some freak or accident, that they became adapted for the purpose. Small dinosaurs may have developed feathers as a way of keeping warm – a form of insulation.

Feathers are now thought to have been common on all kinds of dinosaurs. The reason this has only recently come to light is that feathers are not normally preserved in fossils.

Lots of dino-birds have now been discovered in China's treasure trove of fossils and bones. One of the most famous is Dave, the fuzzy raptor, unearthed in 2000. He was covered from head to tail in a coat of fine feathers, although they weren't designed for flight.

The final part of the bird riddle remains unsolved. How and when did they adapt their insulating feathers into wings for flight? Did they jump from the trees after spying a tasty meal from on high, swooping down to snatch their prey? Or did they run along the ground, perhaps trying to escape some other hungry beast, and flap up to safety? No one is certain, although another recent fossil from China's "Pompeii", a microraptor, suggests the "top-down" theory, because it has both the right kind of feathers for flight and the right sort of claws for climbing trees. But just how and when its feathers of flight evolved is still a mystery, whose answers probably lie somewhere in rocks still waiting to be found.

Start your day with The Independent, sign up for daily news emails
Have you tried new the Independent Digital Edition apps?
ebooks
ebooksA special investigation by Andy McSmith
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Ashdown Group: Client Accountant Team Manager - Reading

Negotiable: Ashdown Group: The Ashdown Group has been engaged by a highly resp...

Recruitment Genius: Account Manager

Negotiable: Recruitment Genius: You will also work alongside their seasoned sa...

Recruitment Genius: Assistant Property Manager

£15000 per annum: Recruitment Genius: Are you looking for your first step into...

Recruitment Genius: Mechanical Design Engineer

£25000 - £40000 per annum: Recruitment Genius: This innovative company working...

Day In a Page

General Election 2015: The masterminds behind the scenes

The masterminds behind the election

How do you get your party leader to embrace a message and then stick to it? By employing these people
Machine Gun America: The amusement park where teenagers go to shoot a huge range of automatic weapons

Machine Gun America

The amusement park where teenagers go to shoot a huge range of automatic weapons
The ethics of pet food: Why are we are so selective in how we show animals our love?

The ethics of pet food

Why are we are so selective in how we show animals our love?
How Tansy Davies turned 9/11 into her opera 'Between Worlds'

How a composer turned 9/11 into her opera 'Between Worlds'

Tansy Davies makes her operatic debut with a work about the attack on the Twin Towers. Despite the topic, she says it is a life-affirming piece
11 best bedside tables

11 best bedside tables

It could be the first thing you see in the morning, so make it work for you. We find night stands, tables and cabinets to wake up to
Italy vs England player ratings: Did Andros Townsend's goal see him beat Harry Kane and Wayne Rooney to top marks?

Italy vs England player ratings

Did Townsend's goal see him beat Kane and Rooney to top marks?
Danny Higginbotham: An underdog's tale of making the most of it

An underdog's tale of making the most of it

Danny Higginbotham on being let go by Manchester United, annoying Gordon Strachan, utilising his talents to the full at Stoke and plunging into the world of analysis
Audley Harrison's abusers forget the debt he's due, but Errol Christie will always remember what he owes the police

Steve Bunce: Inside Boxing

Audley Harrison's abusers forget the debt he's due, but Errol Christie will always remember what he owes the police
No postcode? No vote

Floating voters

How living on a houseboat meant I didn't officially 'exist'
Louis Theroux's affable Englishman routine begins to wear thin

By Reason of Insanity

Louis Theroux's affable Englishman routine begins to wear thin
Power dressing is back – but no shoulderpads!

Power dressing is back

But banish all thoughts of Eighties shoulderpads
Spanish stone-age cave paintings 'under threat' after being re-opened to the public

Spanish stone-age cave paintings in Altamira 'under threat'

Caves were re-opened to the public
'I was the bookies’ favourite to be first to leave the Cabinet'

Vince Cable interview

'I was the bookies’ favourite to be first to leave the Cabinet'
Election 2015: How many of the Government's coalition agreement promises have been kept?

Promises, promises

But how many coalition agreement pledges have been kept?
The Gaza fisherman who built his own reef - and was shot dead there by an Israeli gunboat

The death of a Gaza fisherman

He built his own reef, and was fatally shot there by an Israeli gunboat