About Me

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Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Tuesday 19 August 2014

There Be Dragons!

There certainly be! (OK, there certainly are...). Some 350 species of them in fact, found across Africa (and slightly into Europe), Asia and Australia. This family, Agamidae, is a 'sister' family to the iguana family (Iguanidae) of the Neotropics and some of the Pacific and, strangely, Madagascar. It's a funny thing, but this rather odd distribution of the iguanas neatly fits into the gaps left by the dragons; where dragons are, iguanas aren't, and vice versa.
Bearded Dragon Pogona barbata, Eyre Peninsula, South Australia.
This smallish dragon (ie a young one - adults can be over 50cm long) shows the
characters which immediately distinguish the family. They have strong clawed legs on which
they stand clear of the ground, and have rough, even spiny, scales which don't overlap each other.
The tail is long and whiplike, and doesn't regrow if broken (unlike a skink's for instance).
This Central Bearded Dragon Pogona vitticeps, Windorah, South-west Queensland,
was too cold to run away - the usual defence of dragons - allowing a good view of its spiky scales.

Diporhiphora magna (no common name that I know of), Litchfield NP, south-west of Darwin.
The long whippy dragon tail is very pronounced in this species.
Their family is an old one - indeed, although we regard them as lizards, they (and the iguanas) are less closely related to other lizards than snakes are. One character not visible in the pictures above is the teeth; dragons have acrodont teeth, which means they don't have sockets, but are fused at the base to the surface of the jawbone. It's a common feature in fish and frogs, and isn't a very secure system, as teeth break easily. This doesn't mean they don't work perfectly well, and incautious handling of a wild Beardie has left me quite effectively lacerated on more than one occasion!

Nearly all dragons (and all Australian ones) lay soft-shelled eggs. She buries them - there may be as many as 30 - and leaves the young to burrow out again.
Southern Angle-headed Dragon Hypsilurus spinipes laying eggs in a rainforest track, Lamington NP, Queensland.
I've only been lucky enough to see this event once, and a long time ago, hence the indifferent picture
- a scan of a faded old slide.
As mentioned previously, most dragons can run at astonishing speeds, even rising onto their hind legs to do so. One group of Australian dragons is known as 'bicycle lizards' for this behaviour!
Crested Dragon or Bicycle Lizard Ctenophorus cristatus, west of Norseman, Western Australia.
Note the very long powerful hindlegs for running upright.
There is the hint of the bright brick red on this dragon which will characterise him as breeding begins. This too is typical of many dragons. 
Painted Dragon Ctenophorus pictus, Cape Bauer, South Australia.
The handsome blue flush will spread to his face when breeding starts.
Gippsland (Eastern) Water Dragon Intellagama (formerly Physignathus) lesueurii, National Botanic Gardens, Canberra.
There is a healthy population of these beauties adorning the gardens; only old males attain these striking colours.
Like many dragons these lizards climb well, but they also swim powerfully, dropping from a branch into
the water if disturbed. (Mind you, this particular population doesn't get disturbed easily - they will come to outside
tables at the restaurants hoping for dropped scraps!)
 
Rainbow Agama Agama agama, Douala, Cameroon. Only the males attain these superb colours, and only when breeding. At other times they are dull brown, as are females all year round. There is an apparently healthy population
of them on the footpaths and open spaces, including petrol stations, in this huge crowded city.
Blue-headed Tree Agama Acanthocerus atricollis, Queen Elizabeth National Park, Uganda.
Breeding male above, and female (or possibly non-breeding male) below.

Agamas can be very sociable, and interactions are common.
Agamas in open-air restaurant, Waza NP, northern Cameroon.
Gilbert's Dragon or Ta Ta Lizard Amphibolurus gilberti, Bladensburg NP, Queensland.
The curious alternative common name comes from its habit of 'waving' to rivals, as this one is doing,
to indicate that it is in its territory and aware of neighbours.
Like the Ta Ta Lizard, many dragons perch high to watch for both danger and prey - all are carnivores.
Bearded Dragon, Temora, New South Wales.
They can adjust the melanin-bearing cells in the skin to turn almost black to absorb extra sunshine.

Ring-tailed Dragon Ctenophorus caudicinctus, East MacDonnell Ranges, Northern Territory.
Jacky Lizard Amphobolurus muricatus, Mount Tennent, south of Canberra.
A common and very fast-moving small dragon.


Gilbert's Dragon Lophognathus gilberti, Darwin.

Dwarf Bearded Dragon Pogona minor, Lesueur NP, Western Australia.

Tommy Roundhead Diporiphora australis, Mareeba, Queenland, on termite mound.
It is often said that Australia's great lizard diversity is founded on the abundance of termites in arid lands.
One of the most famous dragon lizards is the Frill-necked Lizard Chlamydosaurus kingii of tropical Australia, not to be confused with the Bearded Dragon, though the names are often interchanged.
Frill-necked Lizard, Mareeba Wetlands, northern Queensland.
Spectacular, but not very often seen by visitors as they tend to be only active in the wet season,
when fewer people visit. In the dry winter they spend time in semi-torpor in trees.
And finally, just a couple more arid land dragons.
Spotted Military Dragon Ctenophorus maculatus, Lake Logue NR, Western Australia.

Lined Earless Dragon Tympanocryptis lineata, Bladensburg NP, Queensland.
These heat-lovers can be remarkably well-camouflaged against coloured desert stones.

Thorny Devil Moloch horridus, Desert Park, Alice Springs.
Surely one of the most extraordinary of all dragons; despite appearances, a slow,
harmless ant specialist. More information about this fascinating animal here.
Love your dragons - I certainly do!

BACK ON MONDAY

5 comments:

Susan said...

Wonderful selection of dragons. I greatly enjoyed seeing them all.

Ian Fraser said...

Thanks Susan; haven't heard from you for a while, hope all's well.

Harvey Perkins said...

What a fantastic collection of photos!

Ian Fraser said...

Thanks Harvey. Mostly just a great collection of subjects though...

Susan said...

This is our busiest time of year with work, so blogs take a back seat. On top of that Simon has just had a detached retina, but we've just about sorted out the immediate ramifications of that now.