We report a time-calibrated stratigraphic section in Colorado that contains unusually complete fossils of mammals, reptiles, and plants and elucidates the drivers and tempo of biotic recovery during the poorly known first million years after the Cretaceous–Paleogene mass extinction (KPgE). Within ~100 thousand years (ka) post-KPgE, mammalian taxonomic richness doubled, and maximum mammalian body mass increased to near pre-KPgE levels. A threefold increase in maximum mammalian body mass and dietary niche specialization occurred at ~300 ka post-KPgE, concomitant with increased megafloral standing species richness. The appearance of additional large mammals occurred by ~700 ka post-KPgE, coincident with the first appearance of Leguminosae (the bean family). These concurrent plant and mammal originations and body-mass shifts coincide with warming intervals, suggesting that climate influenced post-KPgE biotic recovery.

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Breeding biology of radio‐tagged Kakapo Strigops habroptilus on Stewart Island was investigated from 1977 to 1988. Some males moved several kilometres from their ranges occupied in the non‐booming season (May‐November) to track‐and‐bowl systems. Occupancy of track‐and‐bowl systems varied markedly from one booming season (December‐March) to another, from no visits in some booming seasons to breeding years when most males occupied their systems nightly. Descriptions and rates of calling for three types of calls by males are given. Breeding probably occurred in 1978, and nests were found in 1981 and 1985, but radio‐tagged females did not nest in 1982‐84 and 1986‐88. Females visit males at track‐and‐bowl systems for mating in mid‐summer (January‐February), and then returned to their home ranges to nest. Nests were under thick vegetation, in short holes in banks or rotten trees at ground level. Clutches consisted of 2–4 eggs, and incubation lasted about 25 days. One female left her eggs and young nestling unattended at least once a night for 1–4 hours. Thus, Kakapo eggs and young chicks were very vulnerable to predation by introduced predators. There was no evidence that any male assisted a female during incubation or nestling‐rearing phases. The chicks were brooded by day until about 30 days old, after which the female roosted nearby. The chicks left the nest at about 10 weeks old, but remained nearby for a further month. Phenological observations of Kakapo food plants suggest that to stimulate and sustain breeding, Kakapo on Stewart Island are dependent upon abundant fruit from a few irregularly mast‐fruiting tree species.

An intraspecific phylogeny was established for the New Zealand short-tailed bat Mystacina tuberculata using a 2,878-bp sequence alignment from multiple mitochondrial genes (control region, ND2, 12S ribosomal RNA [rRNA], 16S rRNA, and tRNA). The inferred phylogeny comprises six lineages, with estimated divergences extending back between 0.93 and 0.68 million years to the middle Pleistocene. The lineages do not correspond to the existing subspecific taxonomy. Although multiple lineages occur sympatrically in many populations, the lineages are geographically structured. This structure has persisted despite repeated cycles of range expansion and contraction in response to climatic oscillations and catastrophic volcanic eruptions. The distribution of lineages among populations in central North Island indicates that a hybrid zone was formed by simultaneous colonization from single-lineage source populations inhabiting remote forest refugia. The observed pattern is not typical of microbats, which because of their high mobility generally exhibit low levels of genetic differentiation and geographic structure over continental ranges. Although lineages of M. tuberculata occur sympatrically in many populations, genetic distances between them are sufficiently large to suggest that they may be considered evolutionary significant units or taxonomic subspecies.

Short-tailed bats Mystacina tuberculata were widespread throughout the forest that dominated prehuman New Zealand, but extensive deforestation has restricted them to scattered populations in forest fragments. In a previous study, the species' intraspecific phylogeny was investigated using multiple mitochondrial gene sequences. Six phylogroups were identified with estimated divergences of 0.93-0.68 Ma. In the current study, the phylogeographical structure and demographic history of the phylogroups were investigated using control region sequences modified by removing homoplasic sites. Phylogeographical structure in the North Island was generally consistent with an isolation-by-distance dispersal model. Coalescent-based analyses (i.e. mismatch distributions, skyline plots, lineage dispersal analysis and nested clade analysis) indicated that the three phylogroups found in central and southern North Island expanded before the last glacial maximum, presumably during interstadials when Nothofagus forest was most extensive. Genetic structure within a central North Island hybrid zone was consistent with range expansion from separate refugia following reforestation after catastrophic volcanic eruptions. Phylogeographical structure in the South Island was consistent with southern populations originating during rapid southward range expansion from refugia in northern South Island following postglacial reforestation of the South Island 10-9 kya.