Noone has described in detail the year-round habits and reproductive cycle of a North American bat. The important studies of Guthrie (1933a and b), Guthrie and Jeffers (1938), Reeder (1939), Miller (1939), and Wimsatt (1944a deal with only a part of the reproductive cycles of the species treated, and the almost complete annual cycle of Tadarida cynocephala described by Sherman (1937) is marred by the disappearance of these bats at the critical period of copulation and ovulation. Study of the works cited above reveals that the usual pattern of reproduction of vespertilionid bats in eastern and central North America, as in Europe, is as follows: copulation in the autumn near the time of entering hibernation in caves, storage of sperm by both males and females during long periods of hibernation, and ovulation within a few days of emergence from hibernation in the spring. When brought from hibernation into a warm laboratory early in the spring, females will ovulate within a few days and become pregnant, even when separated from males.It is clear that the most remarkable aspect of bat reproduction-spenn storage and delayed ovulation-is closely related to the phenomenon of hibernation. To us it seemed logical, therefore, to expect different reproductive behavior among bats living in a mild climate in California where long periods of hibernation were not known or expected. What reproductive modifications might be found that would accomodate a light and interrupted winter sleep?The bat chosen for our study was the western lump-nosed bat, Corynorhinus rafinesquei intermedius, This subspecies ranges from southern California north and east into Oregon, Washington, Nevada, and Idaho. Other subspecies are found along the northwest coast and into Canada, south into Mexico and Lower California, and east nearly to the east coast. Except in a few instances noted otherwise, the specimens used in this report are of C. r. intermedius taken in central or northern California, chiefly in Marin, Napa, Lake, and Shasta counties. We have not followed Dalquest (1947) in calling specimens from Marin County C. r. townsendi.We were fortunate in our pursuit of Corynorhinus to capture numerous specimens of each sex in every month of the year. This collection coupled with the important information made available by the banding operations initiated by

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Understanding how animal populations have evolved in response to palaeoenvironmental conditions is essential for predicting the impact of future environmental change on current biodiversity. Analyses of ancient DNA provide a unique opportunity to track population responses to prehistoric environments. We explored the effects of palaeoenvironmental change on the colonial tuco-tuco ( Ctenomys sociabilis ), a highly endemic species of Patagonian rodent that is currently listed as threatened by the IUCN. By combining surveys of modern genetic variation from throughout this species' current geographic range with analyses of DNA samples from fossil material dating back to 10 000 ybp, we demonstrate a striking decline in genetic diversity that is concordant with environmental events in the study region. Our results highlight the importance of non-anthropogenic factors in loss of diversity, including reductions in smaller mammals such as rodents.

Over a period of 7 years the biology and phenotypic variability of Chusquea culeou were studied at 5 locations in cool temperate forests of southern Argentina. Excavated rhizomes had an average of 1.1 successful rhizome buds, and an average of 2.1 years elapsed between successive generations of rhizomes. Rhizome buds usually develop within the first four years after a rhizome forms. Height, volume and weight of a culm can be calculated from its diameter 1 m above the ground. Culm size, length of foliage leaf blades, and pattern of secondary branching differed among study sites. Dead culms were numerous and commonly remained erect for more than 7 years after dying. New culm shoots appear in spring and reach full size within a few months. Shoots can grow more than 9 cm/day. Less than half of the shoots survived a year; most were killed by moth larvae. Multiple primary branch buds emerge through the culm leaf sheaths in the second spring. The mean number of branch buds at mid-culm nodes varied between 34.8 and 81.5, and the mean number of primary branches was between 22.8 and 40.8. Number and length of branches, and number and length of foliage leaf blades at each node is related to the position of the node on a culm. Most branches grow about 3 cm and produce 1 to 3 foliage leaves annually. Foliage leaf blades generally live 2 years or more; few survive 6 years. Relative lengths of foliage leaf blades and their spacing along a branch permit recognition of annual cohorts.Both gregarious and sporadic flowering have been reported, and every year a few isolated plants flower and die. Length of the life cycle is unknown. Seedlings require up to 15 years to produce culms of mature size. Foliage branches may live more than 23 years, and culms may survive 33 years. Extensive loss of new shoots to predation suggests that gregarious flowering may be driven by a need to escape parasitism. C. culeou clumps expand slowly. Average annual rate of increase of the number of live culms in a clump was 4.6?o. Methods of seed dispersal are undocumented. A dense stand of Chusquea culeou had an estimated phytomass of 179 tons/hectare (dry weight), 28 ?o of which was underground. Net annual production was about 16 t/ha dry weight.