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,” says Winkler, 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,” Winkler explains. “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.”

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,” explains Emanuel Tschopp. “The consistency in Camarasaurus tooth wear suggests they may have migrated seasonally to access the same resources.”

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,” concludes André Saleiro. These findings also guide his future research: “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.”

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.” 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,” says Winkler. Tschopp adds: “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.”

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,” says Winkler. “Our tools are getting better – and so is our understanding of what life back then was really like.” Tschopp agrees: “We’re still at the beginning with this method – but combining palaeontology, modern technology and interdisciplinary collaboration opens up fascinating insights into ancient worlds.”

Original publication:

Nature Ecology and Evolution

“Dental microwear texture analysis reveals behavioural, ecological, and habitat signals in Late Jurassic sauropod dinosaur faunas”, to be published here:

https://www.nature.com/articles/s41559-025-02794-5