The emergence and demise of giant sloths
The emergence of multi-tonne herbivores is a recurrent aspect of the Cenozoic mammalian radiation. Several of these giants have vanished within the past 130,000 years, but the timing and macroevolutionary drivers behind this pattern of rise and collapse remain unclear for some megaherbivore lineages. Using trait modeling that combines total-evidence evolutionary trees and a comprehensive size dataset, we show that sloth body mass evolved with major lifestyle shifts and that most terrestrial lineages reached their largest sizes through slower evolutionary rates compared with extant arboreal forms. Size disparity increased during the late Cenozoic climatic cooling, but paleoclimatic changes do not explain the rapid extinction of ground sloths that started approximately 15,000 years ago. Their abrupt demise suggests human-driven factors in the decline and extinction of ground sloths.
Authors
- Max C. Langer (ORCID: https://orcid.org/0000-0003-1009-4605)
- Eduardo M. Soto (ORCID: https://orcid.org/0000-0001-6500-5978)
- M. Susana Bargo (ORCID: https://orcid.org/0000-0002-8380-8800)
- Ignacio M. Soto (ORCID: https://orcid.org/0000-0003-2589-826X)
- Rachel E. Narducci (ORCID: https://orcid.org/0000-0001-9744-0560)
- Alberto Boscaini (ORCID: https://orcid.org/0000-0002-8666-9340)
- Gerardo De Iuliis
- Juan L. Cantalapiedra (ORCID: https://orcid.org/0000-0003-0913-7735)
- Néstor Toledo (ORCID: https://orcid.org/0000-0002-6833-3165)
- Timothy J. Gaudin (ORCID: https://orcid.org/0000-0003-0392-5001)
- François Pujos (ORCID: https://orcid.org/0000-0002-6267-3927)
- Daniel Casali (ORCID: https://orcid.org/0000-0002-0100-3735)
- Sergio F. Vizcaı́no (ORCID: https://orcid.org/0000-0001-5197-9472)
Institutions
- Florida Museum of Natural History (US)
- Museum für Naturkunde (DE)
- Consejo Nacional de Investigaciones Científicas y Técnicas (AR)
- University of Tennessee at Chattanooga (US)
- Universidade de São Paulo (BR)
- University of Toronto (CA)
- Universidad de Alcalá (ES)
- Royal Ontario Museum (CA)
- Museo Nacional de Ciencias Naturales (ES)
- Comisión de Investigaciones Científicas (AR)
- Fundación Ciencias Exactas y Naturales (AR)
- Universidad Nacional de La Plata (AR)
Publication Details
- Journal
- Science
- Published
- 2025-05-22
- DOI
- https://doi.org/10.1126/science.adu0704
- Citations
- 11
- Primary Topic
- Evolution and Paleontology Studies
- Type
- article
- Field-Weighted Citation Impact
- 47.62