Introduction
Hidden beneath the lush forests and mountainous terrain of
modern Taiwan lies a surprising truth: this island’s landscapes were once
radically different. A recent groundbreaking study reveals that during the
Pleistocene epoch, parts of Taiwan and the surrounding strait were not
dominated by dense, cool temperate forests, but by a warm, dry
savanna-grassland ecosystem. The clue? Fossil teeth from the giant
straight-tusked elephant, Palaeoloxodon, analysed via stable isotopes. Phys.org+2scimex.org+2
In this article, we will explore the evidence, its implications for Taiwan’s
natural history, and why this matters for understanding changing ecosystems and
our current environment.
Fossil Evidence & What It Tells Us
Elephant Teeth and Isotope Analysis
Researchers from National Museum of Natural Science and
National Taiwan University analysed enamel from Palaeoloxodon specimens
recovered near the Taiwan Strait. Their results show:
- A
strong signature of C₄ plants in the elephants’ diet — plants that
utilise the C₄ photosynthetic pathway, typically found in warm-season
grasses and open grasslands. Phys.org+1
- Oxygen
isotope analyses suggest freshwater river systems were present and used by
these elephants — evidence of large-scale rivers flowing through what is
now the submerged Taiwan Strait. scimex.org+1
- Juvenile
elephant teeth show weaning behaviours extending to about five or six
years of age — adding insight into the life history of these megafauna. Phys.org+1
These findings combine to paint a picture of a landscape
very different from modern Taiwan.
The Reconstructed Landscape
Instead of the dense subtropical or montane forests we
associate with the island today, the Pleistocene land‐bridge area
likely featured:
- Open
grasslands dominated by C₄ grasses and herbaceous plants.
- Freshwater
rivers and valleys cutting through this grassland terrain.
- Megafauna
adapted to savanna-like habitats, rather than forest browsers.
The tooth evidence suggests the Palaeoloxodon in Taiwan
behaved more like its counterparts in tropical grasslands of India and Africa,
rather than the forest-adapted species seen in Europe or Japan. Phys.org+1
Why This Discovery Matters
- Shifting
Ecological Baselines
Many people view Taiwan’s current lush forests and mountainous ecosystems as “natural” or static. This research reminds us that ecosystems change dramatically over geological time. What is now forest may once have been savanna. Understanding these shifts helps us better appreciate the dynamic nature of Earth’s biosphere. - Biogeography
and Species Adaptation
The fact that Palaeoloxodon in Taiwan had a C₄-grass diet shows adaptation to open habitats — different from other populations at higher latitudes or in different regions. This has implications for our understanding of how species evolve under varying climate and habitat pressures across continents. Phys.org+1 - Paleohydrology
& Land-Bridges
The presence of large freshwater rivers hints at a time when sea levels were lower, and the Taiwan Strait region may have been exposed land that terrestrial fauna inhabited. Understanding these past land bridges is crucial for reconstructing migration pathways and extinction events. TVBS+1 - Modern
Conservation Insights
While human timescales are short relative to geological shifts, the study helps frame how climate, sea levels, and vegetation zones can change. Such knowledge informs current conservation and ecological restoration efforts, reminding us that change is inherent in ecosystems — though of course human-driven change today is very different.
Implications for Taiwan’s Natural History
- This
research provides the first clear reconstruction of a Pleistocene
grassland-river valley ecosystem in Taiwan. scimex.org+1
- It
challenges assumptions that Taiwan’s fauna and flora have always been as
they are now; instead, fauna such as Palaeoloxodon adapted to open savanna
environments once roamed.
- It
opens up questions about what other vanished habitats once existed on the
island, and how past ecosystems influenced the subsequent arrival,
extinction or transformation of species.
Looking Ahead: Questions Raised & Research Frontiers
- What
caused the shift from savanna to the forests we see today in Taiwan?
Likely climate change, sea-level rise, tectonic movements, and vegetation
succession—but details remain to be studied.
- What
other species co-existed in that grassland ecosystem? For example, other
megafauna, predators, and plants adapted to C₄ grasslands.
- How
did human arrival and subsequent ecological changes affect the transition
of ecosystems on Taiwan? Though Palaeoloxodon became extinct long before
large‐scale modern human impact, understanding these
dynamics is relevant for megafaunal extinctions globally.
- Can
this kind of isotope-based palaeoecology be applied more broadly in East
Asia to map vanished ecosystems elsewhere?
Conclusion
The study of elephant tooth enamel from the Pleistocene of
Taiwan reveals that what is today a forested, mountainous island was once a
warm, dry savanna-grassland landscape, with mighty elephants browsing C₄
grasses and rivers running through open terrain. This finding not only adds a
fascinating chapter to Taiwan’s natural history but also provides a striking
example of how ecosystems change with climate, geography, and time.
For readers interested in ecology, palaeontology, or conservation, this
discovery serves as a powerful reminder: the landscapes we see now are just a
snapshot, and deep in the past lie radically different worlds waiting to be
uncovered.
References
- Phys.org
(2025, November 5). Taiwan’s ancient vanished ecosystem: Today’s
forests, elephant teeth show.
Retrieved from: https://phys.org/news/2025-11-taiwan-ancient-ecosystem-today-forests.html - The
Royal Society Open Science (2025). Stable isotope analysis of
Palaeoloxodon elephant teeth reveals Taiwan’s vanished savanna ecosystem.
Published by: The Royal Society.
DOI: https://doi.org/10.1098/rsos.250935 - Scimex
(2025, November 5). Taiwan’s ancient vanished ecosystem revealed by
elephant teeth.
Retrieved from: https://www.scimex.org/newsfeed/taiwans-ancient-vanished-ecosystem-revealed - TVBS
News (Taiwan) (2025, November 5). Taiwan’s ancient elephants reveal
long-lost grassland ecosystem.
Retrieved from: https://news.tvbs.com.tw/english/3036293
