New publication: Does an artificial intelligence recognize the leaf shape?

Leaf shape and AI
The automatic identification of plant species using artificial intelligence (AI) is largely based on the analysis of leaf shapes. However, how these complex structures are interpreted by the AI is often difficult to understand and represents a so-called ‘black box’. In particular, the high variability of leaf shapes within a species, as can be observed in Ranunculus auricomus buttercup, poses a challenge for AI.

Geometric morphometrics
In order to evaluate and better understand the performance of AI-based identification systems, we used geometric morphometrics as a tool of explainable AI (eXplainable AI or XAI). This method enables a detailed quantitative description of shape variations and thus allows a direct comparison between the results of the AI and an established morphometric method.

Experiment
Our focus was on recognizing regional population differences in the golden buttercup. We investigated whether the AI is able to recognize subtle morphological differences between several populations based on basic smartphone images. The results show that the AI can reliably identify characteristic features of the leaves even with complex image backgrounds. The agreement with the results of geometric morphometrics confirms the performance of the AI and underlines the potential of this technology for automated phenotyping in plant research.

Significance of this research
Our study provides important insights for the use of AI in plant identification and opens up new perspectives for biodiversity research. The combination of AI and modern morphometric methods enables a comprehensive analysis of plant traits and thus contributes to a better understanding of the evolution and adaptation of plants to different environmental conditions.

The publication is now freely available: Hodač, L., Karbstein, K., Kösters, L., Rzanny, M., Wittich, H.C., Boho, D., Šubrt, D., Mäder, P. and Wäldchen, J. (2024), Deep learning to capture leaf shape in plant images: Validation by geometric morphometrics. Plant J. https://doi.org/10.1111/tpj.17053

Title image: Ranunculus auricomus, Ladislav Hodač