‘What if we could?’: the role of de-extinction in rebuilding ecosystems
Kids News spoke with leading de-extinction expert Professor Andrew Pask about why he is trying to bring back the Tasmanian tiger and what it takes to build a career in de-extinction
READING LEVEL: ORANGE
Ever wondered what it would be like to bring back an animal species from extinction?
That’s exactly what Professor Andrew Pask has been working on.
The professor in epigenetics*, Colossal scientific advisory board member and head of the The University of Melbourne’s Thylacine* Integrated Genomic* Restoration Research Laboratory (TIGRR) has spent more than 20 years working to sequence the genome* of the Tasmanian tiger – an iconic* Australian marsupial that was driven to extinction by humans in 1936.
The project to bring them back is extremely complex.
“We don’t have a living thylacine cell that we can simply bring back to life. Instead, we study the DNA* of the extinct animal and compare it with the DNA of its closest living relatives,” Prof Pask said.
The process has included sequencing both the thylacine genome and the genomes of all of its closest living relatives, in order to figure out which host species would be the best fit as a surrogate*, as well as gene-editing* and the insertion of thylacine DNA into dunnart DNA.
“DNA is made up of a huge number of tiny instructions,” he said. “Scientists can compare those instructions and work out which ones are different. We can then use gene-editing technology to make changes to living cells.”
While the resulting animal won’t be an exact DNA match for the extinct thylacine, being some kind of hybrid, Prof Pask said it was his team’s goal to “create an animal that is as close as possible to the extinct species.”
“I think of it less as simply ‘bringing an animal back to life’ and more as using science to rebuild the biology* of an animal that we have lost,” he said.
The process has been long and challenging, however there have been many exciting moments – especially when ideas suddenly worked in the lab.
“There have been lots of little moments like this — when I first saw DNA from a thylacine specimen, when I was able to get that extinct DNA to function again in a living animal, when we successfully grow cells and make a change to their DNA or see cells behaving in the way we predicted,” he said. “But perhaps the most exciting part is seeing all the different pieces of science coming together. You can spend years working on one small part of a problem, and then suddenly realise that it could connect with something another scientist has been working on.”
WHY BRING SPECIES BACK?
“De-extinction”* has proved a controversial topic, with some seeing the very term problematic given the process involves using another animal’s DNA. The combination of genetic structures means the thylacine that may eventuate from the project will be a hybrid and not the rebirth of the extinct Tasmanian tiger.
But while it is a mind-blowing topic, there is more to de-extinction than just pushing the scientific boundaries of what is possible.
Each species lost to extinction has had a profound flow-on effect to the ecosystem*, and this has been something that Prof Pask wanted to correct.
“We are losing animals and plants around the world at a very fast rate,” he said. “When a species disappears, we don’t just lose one type of animal — we can also lose an important part of an ecosystem.
“De-extinction research gives us new tools to help restore some of that lost biodiversity*. But I think an equally important goal is using these technologies to help animals that are still alive.
“If we can understand why a species is vulnerable to disease, for example, or help increase genetic diversity* in a small population, we may be able to stop it becoming extinct in the first place.”
The H5N1 strand of bird flu has become an alarming example of what could happen to multiple species of wildlife – as has the Chytrid* fungus.
“We are interested in whether some of the genetic technologies we are developing could eventually help wildlife deal with diseases such as chytrid in amphibians and H5N1 bird flu,” Prof Pask said.
“One thing scientists can do is look at the DNA of animals that are more resistant to a disease and try to understand why they are better protected.
“We are still learning how these systems work, but understanding the genetics of disease resistance could one day give conservation scientists new ways to help vulnerable animals.”
BUILDING A CAREER IN DE-EXTINCTION
Prof Pask said de-extinction was a “team sport” requiring experts from multiple scientific areas of study, such as geneticists*, computer scientists, stem-cell* scientists, developmental biologists, veterinarians, animal scientists – and more.
“There are even engineers who help build new equipment and artificial environments for developing embryos*,” he said. “One of my favourite things about this work is that everyone brings a different piece of the puzzle. The really exciting discoveries happen when those pieces are put together.”
For young scientists interested in conservation and de-extinction, he said it was important to be curious, ask lots of questions and study lots of different subjects.
“And most importantly, find something that you really care about,” he said. “Science can be difficult and sometimes experiments don’t work, but if you’re working on a problem that matters to you, you just keep trying – no matter what.
“The biggest scientific discoveries all started with someone just like you asking, ‘What if we could …?’”
POLL
GLOSSARY
- epigenetics: the study of how the environment changes the way your genes work without your DNA structure being altered
- Thylacine: the Tasmanian tiger, a carnivorous marsupial that once lived on mainland Australia and most recently in Tasmania before being driven to extinction by humans
- Genomic: relating to a genome
- genome: an organism’s complete set of DNA
- iconic: symbolic of a country, culture or era
- DNA: the molecule inside living cells with genetic instructions for the way an organism should be, including what physical features it has
- surrogate: an animal used to host the DNA of the extinct animal in order to help bring it back
- gene-editing: technology that lets scientists alter an animal’s DNA
- biology: the body and how it functions
- de-extinction: the process of trying to recreate an extinct animal’s biology by creating a hybrid animal that is extremely similar using the reconstructed DNA genome of the extinct animal and merging it with that of a host animal
- ecosystem: the interaction of plants, animals and other organisms with the landscape and weather patterns
- biodiversity: the variety of life of Earth
- genetic diversity: the variety of genetic traits within a species in order to strengthen its survival
- Chytrid: a microscopic aquatic fungus that attacks frogs and other amphibians through their skin, causing them to get skin and die
- geneticists: scientists or doctors that study genes and how they are passed down through generations
- stem-cell: unspecialised body cells that can divide and turn into specific cell types like muscle, blood or brain cells
- embryo: an animal in very early stages of cellular development, before it develops organs and limbs
EXTRA READING
How Tassie tigers will be reborn
Wolf pup clones: is this ‘de-extinction’?
Bold plan to bring woolly mammoths back to life
QUICK QUIZ
1. Why are some benefits of de-extinction, according to Prof Pask?
2. When did the thylacine become extinct?
3. What are some of the fields of study involved in de-extinction?
4. In what way could de-extinction research potentially help animals that are still alive?
5. Prof Pask said he was interested in seeing whether some of the genetic technologies he was developing could help in the fight against which two deadly diseases?
LISTEN TO THIS STORY
CLASSROOM ACTIVITIES
1. How scientists begin to bring back an extinct animal
Read through the key points from the Kids News article and create a flow chart of the process scientists have used to try and reconstruct an extinct animal.
Time: allow 20 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking
2. Extension
What could some of the problems be if scientists were able to use DNA and grow cells to reconstruct an extinct animal? Work with a brainstorm and list your top three:
1.
2.
3.
Time: allow 10 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking
VCOP ACTIVITY
Wow word recycle
There are plenty of wow words (ambitious pieces of vocabulary) being used in the article. Some are in the glossary, but there might be extra ones from the article that you think are exceptional as well.
Identify all the words in the article that you think are not common words, and particularly good choices for the writer to have chosen.
Select three words you have highlighted to recycle into your own sentences.
If any of the words you identified are not in the glossary, write up your own glossary for them.
Extension
Find a bland sentence from the article to up-level. Can you add more detail and description? Can you replace any base words with more specific synonyms?
Down-level for a younger audience. Find a sentence in the article that is high level. Now rewrite it for a younger audience so they can understand the words without using the glossary.