Recognition of Conus species using a combined approach of supervised learning and deep learning-based feature extraction

PLoS One. 2024 Dec 9;19(12):e0313329. doi: 10.1371/journal.pone.0313329. eCollection 2024.

Abstract

Cone snails are venomous marine gastropods comprising more than 950 species widely distributed across different habitats. Their conical shells are remarkably similar to those of other invertebrates in terms of color, pattern, and size. For these reasons, assigning taxonomic signatures to cone snail shells is a challenging task. In this report, we propose an ensemble learning strategy based on the combination of Random Forest (RF) and XGBoost (XGB) methods. We used 47,600 cone shell images of uniform size (224 x 224 pixels), which were split into an 80:20 train-test ratio. Prior to performing subsequent operations, these images were subjected to pre-processing and transformation. After applying a deep learning approach (Visual Geometry Group with a 16-layer deep model architecture) for feature extraction, model specificity was further assessed by including multiple related and unrelated seashell images. Both classifiers demonstrated comparable recognition ability on random test samples. The evaluation results suggested that RF outperformed XGB due to its high accuracy in recognizing Conus species, with an average precision of 95.78%. The area under the receiver operating characteristic curve was 0.99, indicating the model's optimal performance. The learning and validation curves also demonstrated a robust fit, with the training score reaching 1 and the validation score gradually increasing to 95 as more data was provided. These values indicate a well-trained model that generalizes effectively to validation data without significant overfitting. The gradual improvement in the validation score curve is crucial for ensuring model reliability and minimizing the risk of overfitting. Our findings revealed an interactive visualization. The performance of our proposed model suggests its potential for use with datasets of other mollusks, and optimal results may be achieved for their categorization and taxonomical characterization.

MeSH terms

  • Animal Shells / anatomy & histology
  • Animals
  • Conus Snail*
  • Deep Learning*
  • Image Processing, Computer-Assisted / methods
  • ROC Curve
  • Supervised Machine Learning

Grants and funding

This work has been supported by Higher Education Commission, Pakistan via grant No. 20-15051/NRPU/R&D/HEC/2021. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.