Polar wildfires and conifer serotiny during the Cretaceous globalhothouse

• Several highly effective fire-adaptive traits first evolved among modern plants duringthe mid-Cretaceous, in response to the widespread wildfires promoted by anomalously highatmospheric oxygen (O2) and extreme temperatures. Serotiny, or long-term canopy seedstorage, is a fire-adaptive strategy common among plants living in fire-prone areas today,but evidence of this strategy has been lacking from the fossil record. Deposits of abundantfossil charcoal from sedimentary successions of the Chatham Islands, New Zealand, recordwildfires in the south polar regions (75°–80°S) during the mid-Cretaceous (ca. 99–90 Ma).Newly discovered fossil conifer reproductive structures were consistently associated withthese charcoal-rich deposits. The morphology and internal anatomy as revealed by neutrontomography exhibit a range of serotiny-associated characters. Numerous related fossils fromsimilar, contemporaneous deposits of the Northern Hemisphere suggest that serotiny was akey adaptive strategy during the high-fire world of the Cretaceous.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Multidisciplinär geovetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geosciences, Multidisciplinary (hsv//eng)

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Annan geovetenskap och miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Other Earth and Related Environmental Sciences (hsv//eng)

Keyword

Fossil plants

palaeobotany

fire adaptation

charcoal

hothouse Earth

oxygen

Gondwana

Ecosystems and species history

Ekosystem och arthistoria

The changing Earth

Den föränderliga jorden

Publication and Content Type

ref (subject category)

art (subject category)