Photo of teeth in a jaw section of Giraffatitan from Tanzania (Museum für Naturkunde Berlin, MB.R.2180.20.5). The light-coloured area is the dentin, which has been exposed by tooth wear.
Image Credit: Jan Kersten, Freie Universität Berlin, Fachrichtung Paläontologie.
An international team of researchers, led by Dr Daniela E. Winkler (postdoctoral researcher at Kiel University), Dr Emanuel Tschopp (visiting scientist at the Leibniz Institute for the Analysis of Biodiversity Change and research associate at Freie Universität Berlin), and André Saleiro (PhD student at NOVA University Lisbon), has shed new light on the diet and movements of the 150-million-year-old long-necked dinosaur, Giraffatitan.
By using high-resolution microscopy to examine patterns of microscopic wear on fossilised teeth, the team could reconstruct not only what Giraffatitan ate, but also how it foraged and where it roamed. The results show that these enormous sauropods fed on a wide range of vegetation, from soft leaves to tougher plant material, indicating a flexible feeding strategy. The wear patterns also suggest that the animals migrated across different habitats, rather than remaining in one area, allowing them to exploit seasonal changes in plant availability. This paints a picture of a highly adaptable browser, capable of sustaining its gigantic size by ranging widely across the Jurassic landscape.
In many ways, their lifestyle resembles that of today’s elephants or giraffes, which travel long distances to reach food and switch between different types of vegetation depending on what is available. Like elephants stripping branches or giraffes plucking leaves from the tops of trees, Giraffatitan used its immense neck to access food that other animals could not, helping to reduce competition and maintain the balance of its ecosystem.
They also represent an interesting example of convergent evolution where two unrelated species, in this case a dinosaur and giraffes, converge on the same solution to the same environmental problem - how to reach the leaves at the top of tall trees, so avoiding competition with other browsing animals - long necks and long front legs.
As ever, such discoveries are impossible to reconcile with creationist notions of a young Earth, supposedly only 6,000–10,000 years old. Yet this is merely one more example of the widening gulf between the reality uncovered by science and the superstitions preserved in ancient texts. These texts, after all, were written by Bronze Age pastoralists who imagined the universe as a flat disc beneath a dome, bounded by the few square miles they could walk in a couple of days across the Canaanite hills.
Background^ Giraffatitan.The full study is reported in an open-access paper in Nature Ecology & Evolution and summarised in a Freie Universität Berlin press release.
- Name meaning: “Giraffe giant” – named for its extremely long neck, reminiscent of a giraffe’s.
- Time period: Late Jurassic, about 150 million years ago.
- Location: Fossils discovered in the Tendaguru Formation, Tanzania (then German East Africa).
- Size:
- Length: up to 22–26 metres
- Height: around 12 metres at the head
- Weight: estimated 30–40 tonnes
- Group: A sauropod dinosaur (closely related to Brachiosaurus). Once thought to be a species of Brachiosaurus, but now generally recognised as a distinct genus.
- Distinctive features:
- Extremely long neck and forelimbs longer than hindlimbs, giving a giraffe-like stance.
- Small skull with nostrils set high on the head (once thought to indicate an aquatic lifestyle).
- Lifestyle: Herd-living, migratory browser, feeding on a variety of plants from treetop foliage to mid-level vegetation.
- Outdated ideas: Early palaeontologists suggested sauropods were swamp-dwellers, using high-placed nostrils like snorkels. This has been overturned: bone structure shows they were fully terrestrial, trackways show confident movement on land, and lung pressure would have made deep-water living impossible.
- Scientific importance: One of the best-known sauropods from Africa and among the largest land animals ever to walk the Earth.
What Dinosaur Teeth Reveal About Life 150 Million Years Ago
What did long-necked dinosaurs eat – and where did they roam to satisfy their hunger? A team of researchers has reconstructed the feeding behaviour of sauropods using cutting-edge dental wear analysis. Their findings, published in Nature Ecology and Evolution, show that microscopic enamel wear marks provide surprising insights into migration, environmental conditions, and niche distribution within ecosystems from 150 million years ago.
How did massive dinosaurs live during the Jurassic period? What did they eat, how did they share their habitats – and did they perhaps migrate seasonally? These questions have been explored by an international team of researchers led by Dr Daniela E. Winkler, a postdoctoral researcher at Kiel University, Dr Emanuel Tschopp, visiting scientist at the LIB and research associate at Freie Universität Berlin, and André Saleiro, PhD student at NOVA University Lisbon. Their new study employs an unusual method: using wear marks on fossilised teeth as a window into the past.
I still find it fascinating that microscopic scratches on fossil teeth can tell us so much about diet and even behaviour.
Dr Daniela E. Winkler, co-lead author
Zoological Institute
Kiel University, Kiel, Germany.
Winkler [is] an expert in the applied methodology. The technique, known as Dental Microwear Texture Analysis (DMTA), was originally developed by a research group led by LIB scientist Professor Thomas Kaiser for studying mammals. The current study, published in Nature Ecology and Evolution, marks the first systematic application of the method to sauropods. The analyses were carried out in the laboratories of the LIB.
Tooth Enamel as an Environmental Archive
The team analysed 322 high-resolution 3D scans of tooth surfaces from three geological formations that are famous for their dinosaur fossils: the Lourinhã Formation in Portugal, the Morrison Formation in the USA, and the Tendaguru Formation in Tanzania. All the teeth came from a total of 39 individuals. Samples were taken directly from original teeth or from high-resolution silicone moulds.
We’re talking about structures at the micrometre scale. These tiny wear marks results from the interaction between tooth and food – they reveal what the animals had eaten in the last days or weeks of their lives.
Dr Daniela E. Winkler.
Surprising Differences between Species and Regions
The statistical analyses revealed clear differences between various sauropod groups and their localities oder geographic regions. Particularly striking was the high variability in wear patterns among the flagellicaudatans – a group of long-tailed sauropods that includes the well-known Diplodocus. This heterogeneity suggests that these animals had access to a variety of food sources and displayed generalist feeding behaviour.
A particular surprise was that Camarasaurus specimens from both Portugal and the USA had highly uniform wear patterns. Such consistency in microwear is unlikely to be explained solely by uniform plant availability – rather, it indicates that these dinosaurs deliberately sought out the same preferred food sources throughout the year.
The climate at the time in both Portugal and the USA was highly seasonal, so certain plants likely weren’t available year-round. The consistency in Camarasaurus tooth wear suggests they may have migrated seasonally to access the same resources.
Dr. Emanuel Tschopp, co-lead author.
Now: Department of Vertebrate Paleontology
American Museum of Natural History, New York, USA.
Formerly: Centre for Taxonomy and Morphology
Leibniz Institute for the Analysis of Biodiversity Change
Museum of Nature, Hamburg, Germany.
Things were different with the titanosauriforms from Tanzania, whose teeth showed significantly more intense and complex wear. The researchers interpret this as a result of specific environmental conditions: the Tendaguru Formation featured tropical to semi-arid climates and nearby was a large desert belt, from where quartz sand was probably often blown onto plants these sauropods ate. This sand-contaminated diet likely caused the highly abrasive wear patterns seen on the teeth.
Climate, Not Plant Variety, as the Key Factor
There were also clear differences between the regions themselves: teeth from Tanzania were consistently more heavily worn than those from Portugal or the USA. The crucial influencing factor? Climate.
One of the most interesting aspects of this work is that we were able to relate differences in dental wear patterns to palaeogeography and the habitat preferences of different sauropod faunas. The study showed me how to approach my ongoing work on niche partitioning in herbivorous dinosaurs – by focusing on specific palaeo-environments to better understand the ecological relationships within species groups, and how these differences evolved across ecosystems.
André Saleiro, co-author.
GeoBioTec
NOVA School of Science and Technology
University NOVA of Lisbon, Caparica, Portugal.
For Emanuel Tschopp, this is also one of the most exciting elements of the research:
With these microscopic traces, we can suddenly make behavioural statements about these enormous extinct animals. Migration, specialisation, niche use – it all becomes tangible.
Dr. Emanuel Tschopp.
Another notable aspect: wear patterns differed depending on the area of the tooth – on the side (buccal) or on the chewing surface (occlusal). These differences were accounted for in the analysis to avoid distortion.
Relevance for Biodiversity Research
This study provides not only new insights into the lives of individual dinosaur species but also contributes to a broader understanding of palaeoecological relationships. Niche partitioning, climate-driven adaptations, and potential competition avoidance can thus be identified even in fossilised ecosystems.
We demonstrate that ecological principles like niche formation and migration behaviour were important not just today, but already 150 million years ago. The sauropods of the Morrison Formation show enormous species diversity – and that diversity was only possible because the species behaved differently and occupied different dietary niches.
Dr Daniela E. Winkler.
Looking Ahead: More Teeth, More Knowledge
The research is far from over. Future studies aim to explore whether juvenile and adult sauropods differed in their diets, or how dwarf species such as Europasaurus from Lower Saxony adapted to their specific island environment. Saleiro is already working on an expanded dataset for the Portuguese fauna, including other herbivorous dinosaurs.
What excites me is that we can keep refining this method – and every new sample adds another piece to the puzzle. Our tools are getting better – and so is our understanding of what life back then was really like.
Dr Daniela E. Winkler.
We’re still at the beginning with this method – but combining palaeontology, modern technology and interdisciplinary collaboration opens up fascinating insights into ancient worlds.
Dr. Emanuel Tschopp.
Publication:
AbstractOnce again, we see how modern science continues to uncover the deep past of life on Earth with ever greater precision, while creationism remains trapped in the myths and misunderstandings of ancient herders. From the microscopic wear on the teeth of a long-extinct giant, researchers can reconstruct behaviour, ecology, and even patterns of movement across landscapes more than 150 million years ago.
Most faunas from the Mesozoic era were dominated by sauropod dinosaurs, the largest terrestrial animals to ever exist. These megaherbivores were remarkably diverse and widely distributed. Here we study three Late Jurassic faunas from the USA, Portugal and Tanzania, each approximately 150 million years old, which are known for their extreme sauropod diversity. Whereas general taxonomic composition was similar in these three faunas, the major clades differed in relative abundance. Moreover, their depositional strata record distinct climatic regimes. Using dental microwear texture analysis, we investigated the impact of these climate regimes and the resulting food availability on the different sauropod taxa. Wear patterns in camarasaurid macronarians show minimal variation across different climate regimes, supporting previous studies suggesting that these animals migrated to follow their preferred climate niche and food source. North American camarasaurids show similar wear patterns to those of Portuguese turiasaurs, another broad-crowned taxon, which did not exist in the Jurassic of North America. By contrast, where camarasaurids and turiasaurs co-occurred in Portugal, their microwear patterns are distinct, suggesting niche differentiation to avoid ecological competition between these two clades. Flagellicaudatan diplodocoids display highly variable wear patterns, indicating limited migration (and therefore seasonal variation in diet), which aligns with observed biogeography patterns in the USA. Early-branching titanosauriforms show highly distinct wear patterns between different climate regimes, which can probably be attributed to different abrasive loads in the respective habitats. Our results demonstrate that dental microwear texture analysis not only records dietary preferences but also reveals behaviour such as competition and migration related to dietary niches in past ecosystems.
Main
Late Jurassic ecosystems across the planet were dominated by sauropod dinosaurs in terms of size and body mass contribution1. The three best-known and represented Late Jurassic faunas are from the USA, Tanzania and Portugal. These sauropod faunas had very similar taxonomic compositions, with brachiosaurid macronarians and diplodocoids occurring in all three. The North American and Portuguese faunas furthermore shared the presence of camarasaurid macronarians, whereas turiasaurs and early somphospondylans occur both in Portugal and Tanzania. The Tanzanian fauna further included non-neosauropod mamenchisaurids2,3,4,5,6,7, which are otherwise primarily known from the Jurassic of Asia8,9,10,11. Although generally similar, within-clade species diversity and the abundance of individuals from the distinct taxa are different between the three faunas. Whereas camarasaurid macronarians and diplodocid diplodocoids dominated in the USA12,13,14,15, brachiosaurid titanosauriforms and dicraeosaurid diplodocoids predominated in Tanzania5,16 and turiasaurs in Portugal17,18. The reasons for these unequal distributions of taxon abundance remain poorly understood.
~ As the largest terrestrial megaherbivores that ever roamed the Earth, sauropods must have greatly depended on plant productivity and availability. Similarly to sauropods, major plant groups were distributed globally during the Late Jurassic, with conifers forming the canopy together with ginkgoes. Tree ferns reached intermediate heights, whereas other ferns, seed ferns, cycads and horsetails usually composed the understorey. The only notable difference between the floras of the three sauropod-bearing formations was the absence of the conifer clade Pinaceae and of horsetails in Tendaguru, where also cycads were a comparatively minor component of the plant cover19,20,21. Moreover, the relative abundance of the different plant clades differed between the three biomes21, which was correlated to distinct climate regimes.
Palaeoclimatic reconstructions indicate different climatic conditions in these three regions during the Late Jurassic20,22,23,24,25. The western USA was reconstructed as semi-arid to arid, with a mean annual temperature ranging between 12 °C and 30 °C, depending on latitude22,25 and probably strong seasonality24. Mean annual precipitation was found to be higher in Portugal and Tanzania compared with the USA, suggesting a more humid climate than in the USA24,25. In Portugal, mean annual temperature ranged between 18 °C and 24 °C, whereas it was considerably warmer, with 24–30 °C, in Tanzania25. Seasonality was probably strong in Tanzania as well, with wet winters22,26 and dry summers20, corresponding to a monsoon-type climate25. We hypothesize that these different climate regimes probably controlled forage availability, which in turn shaped distribution and abundance of different sauropod taxa adapted for foraging on specific plant taxa. Furthermore, we propose that large-bodied herbivores in such habitats affected by seasonality either adopted a generalist feeding strategy, using diverse dietary resources in the same place year-round, or depended upon seasonal migration if they had a narrower dietary niche.
Strong niche partitioning between major sauropod groups has been suggested on the basis of their distinct skull shapes and tooth morphologies, and the posture of the neck and forelimbs7,18,27,28,29,30,31,32,33,34,35,36,37,38,39,40. However, morphology can provide only general information about possible feeding adaptations and is not direct evidence whether a certain dietary resource was actually exploited. A promising avenue to assess niche partitioning in sauropods and other archosaurs is the study of dental microwear as a dietary proxy35,41,42,43,44,45,46. We here use three-dimensional dental microwear texture analysis (DMTA), a semi-automated quantitative approach to evaluate microscopic surface wear of enamel wear facets47,48, as a means to test whether distinct sauropod taxa occupied the same niche in three different geographical areas (Fig. 1) irrespective of climate, and how these food preferences and availability may have shaped sauropod distribution during the Late Jurassic period.
Fig. 1: Sauropod diversity and tooth morphology at the sampled locations.
a, Palaeogeographic map showing the approximate arrangements of continents during the Late Jurassic. Yellow star, North America (Morrison Formation); blue star, Portugal (Lourinhã Formation); and red star, Tanzania (Tendaguru Formation). Silhouettes represent major taxonomic groups of sauropods present in the sampled locations. Taxa that were not available for inclusion into the current study from the respective locations are shown in light grey, those included in the analysis are shown in colour. b, Tooth morphologies for selected clades and phylogenetic tree. All clades except possibly Somphospondyli and Mamenchisauridae could be sampled for the current study. The indeterminate sauropods and macronarians sampled in this study could not be attributed to a less-inclusive clade. Tooth morphologies are shown for well-represented clades (from left to right, Turiasauria, Titanosauriformes, Camarasauridae, Flagellicaudata). Teeth are shown in lingual and buccal view. Approximate sampling areas for occlusal and buccal surfaces are shown in camarasaurid and turiasaur teeth, respectively (grey arrows). Credits: a, Maps are taken from The Paleobiology Database Navigator (https://paleobiodb.org/navigator/) under a CC BY 4.0 license, which uses GPlates as a data source for the maps. GPlates are shared under the GNU software general public license, v.2 (https://www.gnu.org/licenses/old-licenses/gpl-2.0.html). a,b, Silhouettes are from Phylopic (https://phylopic.org). Xinjiangtitan shanshanesis (Mamenchisauridae), created by Jagged Fang Designs under a CC0 1.0 license; Haplocanthosaurus priscus, created by T. M. Keesey under a CC0 1.0 license; Amanzia greppini (Turiasauria), created by T. Dixon under a CC BY 4.0 license; Euhelopus zdanskyi (Somphospondyli), created by DiBgd and modified by T. M. Keesey under CC BY-SA 3.0 license; Giraffatitan brancai (Brachiosauridae), created by S. Hartman under a CC BY-SA 3.0 license; Diplodocus carnegii (Flagellicaudata), created by S. Hartman under a CC BY-SA 3.0 license; Camarasaurus supremus (Camarasauridae), created by M. Wedel under a CC BY-SA 3.0 license. Tooth shapes are modified from ref. 18, Wiley.Winkler, D.E., Tschopp, E., Saleiro, A. et al.
Dental microwear texture analysis reveals behavioural, ecological and habitat signals in Late Jurassic sauropod dinosaur faunas.
Nat Ecol Evol 9, 1719–1730 (2025). https://doi.org/10.1038/s41559-025-02794-5
Copyright: © 2025 The authors.
Published by Springer Nature Ltd. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
By contrast, creationism has nothing to offer beyond denial and distortion. It cannot explain the evidence, it cannot predict discoveries, and it cannot account for the vast timescales revealed in the rocks and fossils beneath our feet. Each new study like this widens the gulf between evidence-based science and the dogma of those who insist the Earth is younger than the ruins of Sumer and Babylon.
Science reveals a world of astonishing depth and complexity, where even the smallest traces — the scratches on a fossil tooth — tell stories that creationist superstition can never hope to match.
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