True blue living fossils

19 August, 2010

Two Australian Lungfish
Two of the Australian Lungfish on display in 600 Million Years: Victoria Evolves at Melbourne Museum.
Image: Benjamin Healley
Source: Museum Victoria

The museum’s preparators create models of prehistoric animals that are so vivid and lifelike that you almost expect the displays to move. But in 600 Million Years: Victoria Evolves, the prehistoric fish do move, because they’re alive!

The Australian Lungfish, Neoceratodus forsteri, is often called a ‘living fossil’ since its basic body form has changed very little in 150 million years. Alongside models of early tetrapods like Acanthostega, three live lungfish are part of the museum’s display about the evolution of land vertebrates. “We’ve had some wonderful moments because visitors think they’re all models,” said Alan Henderson of Live Exhibits. “They sit still for quite a while, with the models next door, but then one of the lungfish moves!” Every few minutes, the fish rise to the water surface to gulp air into their single lungs.

The lungfish came from Macquarie University researcher Professor Jean Joss, who bred them in captivity 16 years ago. They belong to a group called the lobe-finned fish (or Sarcopterygii) that first arose in the Silurian Period around 418 million years ago. Their fleshy, strong fins were the precursor to the basic limb structure shared by all vertebrates, including ourselves. Only a handful of lobe-finned fish survive today; most living bony fish belong to the Actinopterygii or ray-finned fish, such as tuna, salmon and carp.

Professor Joss studies the biology of lungfish because they are the closest living relative to our ancient ancestors. By learning more about lungfish we learn more about all tetrapods (the four-limbed animals with a backbone, namely birds, mammals, reptiles and amphibians). The Australian Lungfish is a protected species and is found only in a few rivers in south-eastern Queensland, so the museum is grateful to Professor Joss for providing three of these rare and amazing creatures. Wild Australian Lungfish populations are falling due to drought, habitat destruction by human activity and invasive fish species.

Since arriving in June, the fish have settled in well and are surprisingly active; as Jessie Sinclair from Live Exhibits explained. “They do enjoy their food. We’re finding they’ve got a decent appetite and spend a lot of time grazing like vacuum cleaners. They seem to polish off anything they can get their mouth around.” The Live Exhibits keepers monitor what each fish eats and hand-feed them earthworms and fish pellets. A bacterial filtration system and regular monitoring ensures the water remains balanced and conditioned for good health.

Their tank is a roomy 2.5m long to give them lots of room to grow. “They’re only in their teens and they have a long way to go,” explained Jessie. “They do a lot better when they live in groups which is why we have three fish.” Australian Lungfish can live for decades and reach over a metre in length. This large tank will suit them for many years before they will require a bigger enclosure.

Comments (2)

sort by
Lex 4 September, 2016 17:14
I was at the museum today and although I enjoy it each time I visit, I couldn't help thinking that the lungfish tank looked far too small for the three animals housed within it. The poor things are well-overdue for a bigger tank, in my opinion, and please give them somewhere to shelter from the tapping fingers of toddlers.
Discovery Centre 8 September, 2016 15:23

Thanks for your comment. We take the welfare and comfort of our animals very seriously, and undertook copious research on the biology and behaviour of Queensland Lungfish before designing the enclosure and determining how to care for this species. In the wild, lungfish are adapted to live in stagnant water and have poor eyesight, remaining stationary for long periods (particularly during the day), and feeding on plants and aquatic animals at night.

Queensland Lungfish have relatively small home ranges and their activity is usually restricted to courtship behaviour and instream flow events in their natural habitat. Otherwise they are reported to be slow-moving and sluggish in the wild. Researchers have found that Queensland Lungfish is a ‘sedentary species, reluctant to move even during times of flood’.

The housing for our lungfish is in excess of the recommended dimensions for this species according to Australian regulations. Many animal species require smaller enclosures than might seem natural, to help with their comfort and security. Animal species that live in burrows or under logs, or shelter in cavities such as tree hollows and rock crevices, or in restricted aquatic habitats, become extremely uncomfortable and stressed in larger spaces, particularly when kept in these spaces for long periods of time. As animal keepers and enclosure designers, we have to avoid the anthropomorphic tendency to project our needs on those of our animals, particularly regarding food quantities and housing size.

But we take your comments on board and thank you for your concerns.

Write your comment below All fields are required

We love receiving comments, but can’t always respond.