RESURRECTION OF THE THYLACINE:
EXPLORING THE SCIENTIFIC PATH TO DE-EXTINCTION

By: Aly Diana

The Thylacine, scientifically known as Thylacinus cyno-cephalus or the Tasmanian Tiger, was an extraordinary carnivorous marsupial and the sole member of the Thy-lacinidae family to survive into modern times. Historical-ly, the Thylacine was widespread across Australia, but its presence on the mainland ceased around 3,000 years ago. Roughly 14,000 years ago, changes in sea levels isolated a population in Tasmania, which persisted until the early 20th century. European settlers viewed the Thy-lacine as a menace to the sheep industry in Tasmania, leading the government to institute aggressive eradication measures, including a bounty of £1.00 for each Thy-lacine killed. As a result, the Thylacine population dwindled rapidly, culminating in the death of the last known individual at the Hobart Zoo in 1936. The species was officially declared extinct in 1982.

The potential resurrection of the Thylacine holds immense ecological value. As a top predator, the Thylacine helped regulate prey populations, curtailing overgrazing and influencing vegetation patterns. Its disappearance disrupted these vital ecological relationships, causing shifts in flora and possibly leading to the proliferation of mesopredators. Reintroducing the Thylacine could balance trophic cascades, maintain predator-prey dynamics, conserve biodiversity, bolster ecosystem services, and assist ecosystems in adapting to anthropogenic changes. The Thyla-cine’s viability for de-extinction is highlighted by its recent extinction, the availability of high-quality DNA, and the persistence of its natural prey and habitat.

Launched more than a decade ago but paused due to lack of funds, the project has witnessed a revival. The Colossal TIGRR Collaboration, operating from 2022 to 2026, combines the expertise of renowned individuals like Harvard University geneticist George Church and tech entrepreneur Ben Lamm of Colossal Biosciences. Additionally, the University of Melbourne’s Andrew Pask leads the Thylacine Integrated Genomic Restoration Research (TIGRR) Lab, which has benefitted from a generous donation from the Wilson Family Trust. While resurrecting the Thylacine is no longer just a dream, the endeavor may still require a decade or longer.

This ambitious project encompasses nine detailed steps across genetics, technology, and ethics, challenging the limits of conservation science.

Step 1: The Blueprint of Return.

The first crucial step in de-extinction is crafting a comprehensive genetic blueprint or genome. The Thylacine genome, unveiled in 2017, is among the best-quality extinct genomes ever produced. This guide holds the instructions for reviving the Thylacine, with ongoing technological advancements in genome sequencing paving the way for further refinement.

Step 2: Kinship Exploration.

The DNA sequences of the Thylacine’s nearest relatives, such as the dunnart or marsupial mouse, have been identified. These species form the groundwork for piecing together the Thylacine genome.

Step 3: Bioinformatics Puzzle.

This step is a sophisticated computational challenge, comparing marsupial genomes to identify the necessary changes for producing a “Thylacine” cell. The TIGRR lab is at the forefront of this complex task.

Step 4: Stem Cells and Progress.

The development of methods to extract stem cells from marsupials, like the fat-tailed dunnart, is in progress in collaboration with the TIGRR lab and the Australian Research Council. These techniques are pivotal for Thylacine de-extinction and also have broader implications for conserving endangered marsupials.

Steps 5 to 7: Assisted Reproduction Advances.

These phases focus on creating assisted reproductive technologies (ART) for marsupials. The TIGRR lab spearheads this initiative, aiming to enable living stem cells to produce embryos suitable for implantation in surrogate species.

Steps 8 and 9: Highlighting the Marsupial Advantage.

Marsupials possess a unique edge in the de-extinction process due to their reproductive method. Given that marsupials birth underdeveloped young that mature in pouches, the prolonged gestation period typical of other mammals can be avoided. For de-extinction, this implies that offspring can be bottle-fed early on, negating the need for surrogate mothers or intricate gestation. These nine steps lay the groundwork for the possible revival of the Thylacine. However, the endeavor extends beyond resurrecting one species—it offers potential advancements in marsupial conservation and technology. The ongoing research is already yielding insights into genetics, stem cell research, and reproductive methods, which can have a lasting impact on the conservation of at-risk species.

The Resurrecting the Thylacine Project ventures into the unexplored convergence of science and ethics. As we embark on this journey, the initiative ignites discussions about our responsibility to Earth’s biodiversity. While debates about resource allocation and ecological consequences continue, the project stands as a testament to humanity’s unique ability to amend past mistakes and thereby influence our planet’s future. As the project evolves, we edge closer to potentially reuniting with a long-gone species, deepening our grasp of genetics and conservation science.

Disclaimer: I am not commenting on the ethical dimensions of this project. This article merely offers a brief overview of years of research, which is not my primary field. Nonetheless, I hope it sparks curiosity, interest, or a glimmer of hope among readers.

Reference

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