The dingo is a canine endemic to Australia.
They’re lithe apex predators, and belong to the Canis genus – the same family that
has wolves, foxes, coyotes and dogs.
But they didn’t evolve in Australia, so where did they come from, and when?
And how closely are they related to dogs?
Before we can understand where and when dingos originally came from, we need to know a bit
about how the Australian and South-East Asian region looked about 18000 years ago.
Back then, Australia and New Guinea were joined in a landmass called Sahul, while much of
South-East Asia was joined into a landmass called Sunda.
Using DNA, it has been shown that the dingo’s ancestors probably first originated in Sunda.
Dingoes share some DNA with dogs, and with wolves.
This means that the dingo’s ancestors could’ve been a result of early domestic dogs and wolves
interbreeding.
It’s hard to say exactly how long ago this happened though.
Scientific studies rely on the mutation rate of DNA to estimate how long ago something
happened.
For example: I can put a cup of ice on the bench, and leave the room.
I know the ice melt, but I don’t know exactly how long it’ll take to change into water.
I can guess it’ll take a few hours, but without knowing the exact temperature of the
room – I’m not 100% sure.
It’s the same with dingo DNA – we know it changes slowly over time, so we can estimate
how long ago something happened by looking at how much the DNA has changed – but we
are not 100% sure how fast it changes.
The dingo’s ancestors spread through Sunda, modern-day South-East Asia.
To get from Sunda to Sahul – they may have had to travel with humans in boats, as there
probably wasn’t an easy way to get from continent to continent, but this just an assumption
and hasn’t been proven.
Once the dingo’s ancestors got to Sahul, they probably arrived in the north first,
which is the bit called New Guinea today.
From there they spread through large amounts of the continent.
It’s hard to say exactly when dingoes entered the Australian part of Sahul.
It’s kind of like putting the ice out on the bench, but this time we have a few more
clues.
Dingo fossils as old as 3500 years have been found in Australia, so we know for sure that
dingos arrived in Australia before then.
Although, it is really hard to find fossils in some biomes because they don’t get preserved
very well, so dingoes probably arrived in Australia even earlier.
Another big clue is Tasmania.
Tasmania is an island off the south coast of mainland Australia.
No dingo fossils have ever been found there.
We know that Tasmania became an island only about 12000 years ago.
So if no dingoes have ever lived in Tasmania, then we know dingoes probably came to Australia
after Tasmania was separated as an island.
But the only thing it proves for sure is that paleobiology is about making the best guess
you can with the evidence that you have.
Dingoes have a close relative in nearby New Guinea, the New Guinean Singing dog.
Dingoes and Singing dogs share a mitochondrial DNA mutation that shows they are closely related,
possibly even originating from the same female ancestor.
What’s really interesting is that if you look at dingoes in Australia today – the
ones in the east and the ones in the northwest have some genetic differences from each other.
The dingoes in the east seem to be more closely related to the New Guinean singing dog, than
the dingoes in the north west are.
Although they both are very similar.
One explanation for this, is that dingoes entered the Australian part of Sahul more
than once.
For example, the first lot of dingoes could have come in and headed west, and then later
on more dingoes came in and headed East.
The eastern dingoes continued to play with the New Guinean ones until Sahul was split
into New Guinea and Australia, about 8 – 10 thousand years ago.
At this point the New Guinean canids diverged, becoming the New Guinean singing dogs, and
the eastern and western populations of dingoes continued to party together in Australia,
staying one species.
The oldest dingo remains ever discovered are about 3500 years old, and curiously, were
found in the south of Australia, even though dingos were thought to have immigrated from
the north.
This implies that once dingoes got to Australia, they probably spread incredibly quickly through
the continent, possibly aided by a commensal relationship with aboriginal people.
Dingo remains from thousands of years ago show a pretty much identical bone morphology
to modern-day dingos.
This proves that dingos are an ancient group of canines, not having greatly changed for
the last few thousand years.
Unlike domestic dogs, dingoes have not been selectively bred.
Ever since European colonial contact with Australia, dingoes have been compared to dogs.
Scientists have been struggling to agree on how to name dingoes.
Many different names for the dingo have been proposed, but recent research suggests that
dingoes should be classed within their own species of the Canis genus, as Canis dingo
– although this is contested by some scientists that believe dingoes should still be classed
within the domestic dog species.
Whether you agree that dingos are a separate species or a subspecies, from analysing their
DNA it’s clear that they have their own particular genetic pool.
Or at least, they did.
For the last few hundred years, many dingoes have been interbreeding with domestic dogs,
and feral dogs.
This problem is so pronounced, that it’s estimated that less than half of Australia’s
wild canids are pure dingoes.
This research conducted in 2011 shows that pure dingoes are found in highest concentration
in the north and centre of the country where around 88% of wild canids are pure dingos,
while almost none are found in the south east, where only 1% of wild canids are pure dingo.
But is it really a problem that dingoes are breeding with dogs?
Well, yes.
And there are a few reasons.
Firstly, dingoes are an apex predator.
In fact, they are THE terrestrial apex predator on mainland Australia.
Apex predators provide an important population control on other animals, which subsequently
effect the surrounding environment.
For example, Australia has a veritable plague of rabbits, of which dingoes are a great predator.
Rabbits negatively impact native environments in Australia, so controlling them is very
helpful.
But it’s not only rabbits that dingoes hunt, it’s also feral cats and foxes, which pose
a tremendous threat to smaller native mammals such as bilbies.
But dingoes eat bilbies too, you say!
Well yes they can, but they’ve been doing so for thousands and thousands and thousands
of years, and presumably reached a good equilibrium whereby bilbies don’t become extinct.
By breeding dingoes with domestic dogs, it’s possible that they lose the equilibrium they
have established with Australian environment, and start causing more harm than good.
Another reason to protect the dingo from breeding with wild or domestic dogs, is that it makes
it much easier to protect the dingo from being hunted or culled.
Currently in many areas of Australia its legal to kill wild dogs, while dingos are often
protected as native species.
However, dingoes that cross-breed with dogs may no longer be protected by these laws.
This has recently become the case in the state of Western Australia, where under proposed
new legislation dingoes are considered to be wild dogs, rather than native animals,
due the level of cross-breeding – and so are not protected as native wildlife.
The story of dingoes in Australia creates as many questions as it answers.
No one knows exactly how or when dingoes arrived, but we can make a good guess.
But regardless of what happened thousands of years ago, dingoes are worth protecting
today.
They’re Australia’s top terrestrial predator, and are a special kind of canid.
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