New insights into the biology of high-latitude Mesozoic trees

The presence in the specimens of both epicormic shoots and traumatic growth zones, combined with the observation of some disorientation of the wood structure in some parts of the trunks, suggest that these trees were growing under more stressful conditions than previously described trees from the Fremouw Formation.

The biology of extinct trees that grew in high-latitude forests during warmer geological periods is of major interest to understand past and future ecosystem dynamics. Decombeix et al. describe a detailed anatomical study of new fossil gymnosperms from the Triassic (ca. 240 my) of Antarctica.

Disrupted growth in the wood of a Triassic trunk
Disrupted growth in the wood of a Triassic (ca. 240 my) trunk from the Central Transantarctic Mountains. These new Antarctic fossils document the first co-occurrence of traumatic growth zones and epicormic shoots in an extinct plant, and provide new information on the biology of trees that grew in high-latitude forests under past greenhouse climates.

The Triassic trees formed epicormic shoots and had traumatic growth zones in their wood indicating that they were subjected to environmental stresses not seen previously from this region. This study provides new insights into aspects of tree growth and response to disturbance in these warm high-latitude forests that have no equivalent today.

Reference List

Decombeix, A.-L., Serbet, R., & Taylor, E. L. (2018). Under pressure? Epicormic shoots and traumatic growth zones in high-latitude Triassic trees from East Antarctica. Annals of Botany, 121(4), 681–689. https://doi.org/10.1093/aob/mcx199