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© 2020 The Royal Society of New Zealand. The New Zealand Fossil Record File, an essentially complete compilation of New Zealand’s known fossil record, with additional records from parts of Antarctica, SW Pacific, and elsewhere, is, to the best of our knowledge, unique. It has developed collaboratively, with contributions from university, government, industry, and avocational paleontologists and geologists. The distinctive Fossil Record Number has become an icon of New Zealand geological literature since inception of the original paper-based archive in the 1940s. Subsequently, the file has been digitised and currently holds >100,000 locality records and >1,000,000 individual taxonomic identifications spanning numerous plant and animal phyla. These numbers are continually growing. The database contains contextual information on geographic location, collection, stratigraphy and lithology of the fossil localities as well as taxonomic analyses that retain original identifications yet accommodate re-assignments. The data have been widely applied, initially for mapping, establishing age, depositional environment, etc., and more recently including in quantitative biostratigraphy, assessing completeness of the fossil record, understanding biodiversity history, extinction risk assessments, and climate analysis. In this paper, we provide a brief overview of the history of the Fossil Record File, indicate the general nature of the data it contains, and showcase a number of innovative applications of this most valuable resource.

Terrestrial methane (CH 4) emissions may have increased during the Paleocene-Eocene Thermal Maximum (PETM; ca. 56 Ma) and promoted additional warming, especially in the high latitudes. Although there is evidence for increased CH 4 cycling in a single Northern Hemisphere site, whether enhanced methane cycling was globally widespread is unknown because there have been no subsequent investigations. The mechanism of CH4 release is also unknown because a direct comparison between temperature and CH 4 cycling has so far not been possible. Here we use biomarkers to reconstruct temperature change and CH 4 cycling in a new PETM-aged succession in New Zealand. Our results indicate that the stable carbon isotopic composition (δ 13C) of bacterial hopanoids decreased to very low values (−60‰) during the onset of the PETM, indicating enhanced consumption of CH 4. These values are much lower than found in modern wetlands and suggest a major perturbation of the CH 4 cycle during the onset of the PETM. Low hopanoid δ 13C values do not persist into the early Eocene, despite evidence for elevated temperatures. This indicates that the terrestrial CH 4 cycle operates differently during transient compared to gradual warming events. Enhanced CH 4 cycling during the PETM may help to resolve the temperature data-model mismatch in the high latitudes and could yield higher estimates of Earth system sensitivity than expected from CO 2alone.

A reconstruction of terrestrial temperature and precipitation for the New Zealand landmass over the past ∼30 million years is produced using pollen data from >2000 samples lodged in the New Zealand Fossil Record Electronic Database and modern climate data of nearest living relatives. The reconstruction reveals a warming trend through the late Oligocene to early Miocene, peak warmth in the middle Miocene, and stepwise cooling through the late Neogene. Whereas the regional signal in our reconstruction includes a ∼5–10° northward tectonic drift, as well as an increase in high altitude biomes due to late Neogene and Pliocene uplift of the Southern Alps, the pattern mimics inferred changes in global ice extent, which suggests that global drivers played a major role in shaping local vegetation. Importantly, seasonal temperature estimates indicate low seasonality during the middle Miocene, and that subsequent Neogene cooling was largely due to cooler winters. We suggest that this may reflect increased Subantarctic influence on New Zealand vegetation as the climate cooled.

Although significant angiosperm diversification occurred during the Cretaceous, the timing of subsequent expansion of flowering plants across austral landscapes is poorly understood due to a lack of continuous records. Our new 100 million year composite pollen record from New Zealand shows a striking temporal separation between diversification and ecological dominance in this group. While Cretaceous diversification was closely followed by an increase in angiosperm frequency, maximum frequency did not occur for another 40 million years, during the Eocene. The two most consistent intervals of floral change over the 100 Myr record occur within the middle Eocene and the middle Miocene. Notable floral changes also occur around the Cretaceous-Paleogene, Paleocene-Eocene, and Pliocene-Pleistocene transitions. These major changes occur in the context of the northward drift of Zealandia across the Antarctic circle, global warming in the early Paleogene, and middle Miocene, and onset of Southern Ocean circumpolar circulation and cooling in the late Paleogene.

We thank Panero for his interest in our paper. However, we consider his interpretations somewhat incomplete and misleading, principally because he reports results using methods that we did not apply in our study, and underestimates the importance of pollen morphological characters in phylogenetic studies. We respond to each of these points with the aim of clarifying his misinterpretations about our paper., Facultad de Ciencias Naturales y Museo