About the Authors

José Miguel Gasulla

Contributed equally to this work with: José Miguel Gasulla, Fernando Escaso

Affiliation Unidad de Paleontología, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain

Fernando Escaso

Contributed equally to this work with: José Miguel Gasulla, Fernando Escaso

fescaso@ccia.uned.es

Affiliation Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain

Iván Narváez

Affiliation Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain

Francisco Ortega

Affiliation Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain

José Luis Sanz

Affiliation Unidad de Paleontología, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: JMG FE IN FO JLS. Performed the experiments: JMG FE. Analyzed the data: JMG FE FO. Contributed reagents/materials/analysis tools: IN FO JLS. Wrote the paper: JMG FE FO IN JLS.