Sprecher
Beschreibung
As components of modern forest ecosystems, woody angiosperms are the legacy of a complex evolutionary history rooted in the Cretaceous. To understand how woody angiosperms rose to global dominance from the Early Cretaceous to the Santonian, we analyzed their fossil wood record based on an exhaustive literature review, focusing on the paleodistribution and regional composition of angiosperm fossil wood. The first records of angiosperm fossil wood date back to the Aptian–Albian. During these stages, woody angiosperms achieved a global distribution and crown groups, such as fabids (Euphorbiaceae), malvids (Anacardiaceae), asterids (Theaceae), and lamiids (Icacinaceae), were present in temperate, subtropical, and tropical regions. A shift occurred during the Santonian marked by an increase in taxonomic diversity, notably within the fabids and malvids in tropical and subtropical climates. Although magnoliids and ANA-grade taxa were distributed at high latitudes, such as Antarctica, during the Santonian, asterids remained concentrated near the Equator. By the end-Cretaceous, woody angiosperms were established across diverse biomes, ranging from temperate to tropical regions. The absence of records in steppe and arid regions may reflect taphonomic and sampling biases rather than an absence of woody angiosperms in these regions. However, this pattern may also suggest that woody angiosperms had not yet emerged or expanded there. We propose that the mid-Cretaceous expansion of humid environments, together with a rise in wildfire frequency created new ecological opportunities for the diversification of woody angiosperms. By exploiting these newly available niches, woody angiosperms may have outcompeted established gymnosperm lineages.