THE OCULAR FUNDUS OF TWO CETACEANS

We provided a water-cornea interface to correct the usual aerial myopia encountered in fundus photography of marine mammal eyes. The 12 Tursiops eyes were consistent for vascular structure, optic papillae, dimensional components and tapetal coloration. Multiple photographs were assembled to produce one ocular fundus typical of Tursiops truncatus and one for Grampus griseus. The eyes have a vestigial hyaloid vessel and an optic disc („blind spot”) that occupies the center of the fundus. The disc is bounded in both species by a vascular structure that is continuous with a (retrobulbar) perineural organ called the ophthalmic rete. The vascular trees of the fundus do not suggest an area of specialization for high resolution. Both species exhibit total tapetalization. Tapetal spectral reflectance did not vary between Tursiops. There was, however, a difference between species in the short wavelength regions of the spectrum.     

Floral species richness,structural diversity and conservation value of vanilla agroecosystems in Madagascar

Agricultural landscapes provide financial livelihoods for farming communities in rural areas. However, such agroenvironments can significantly impact the local floral biodiversity and introduce harmful invasive species to the ecosystem. Despite the prominence of plantations throughout the tropics, their effects on local flora are limited to only a few specific cash crops and geographical regions. Here, we compared the species richness and structural diversity of vegetation in natural forest fragments and three types of vanilla plantation within the Sava region of north-east Madagascar ranging from those within or adjacent to existing forests, to intensively cultivated plantations. We recorded data on plant species abundance, diameter at breast height and canopy cover within multiple sites of each habitat. We used abundance data to calculate species richness indices, and we compared these metrics between habitats. Forested habitats contained a significantly higher floral species richness, structural diversity and more endemic and regionally native species than nonforested, anthropogenic vanilla plantations. However, our results suggest that the high floral species richness and structural diversity of natural forests can be partially achieved in vanilla plantations, depending on the site's management regime; traditionally managed vanilla plantations located close to natural forests can support diverse floral communities. These encouraging findings for plant conservation and sustainable agroforestry in Madagascar suggest that that newly created vanilla plantations and already existing nonforested plantations should endeavour to follow the more traditional forested approach to enhance the future sustainability and promote floristic diversity.     

Biophysical Heterogeneity,Hydrologic Connectivity,and Productivity of a Montane Floodplain Forest

Ecosystems - Floodplains display exceptional variation in habitat type, connectivity, and vegetation structure that make them ideal landscapes in which to address biophysical controls on primary...     

CETACEAN LENS ZONES OF DISCONTINUITY—INDICES OF HEALTH AND DEVELOPMENT

Details of the lenses of eyes in two living Tursiops truncatus and one Grampus griseus were photographed. In the laboratory the lens cortex could be retro-illuminated by a fundus camera and spatially periodic stria could be visualized, in large part because of the highly developed tapetum of the cetacean eye. Varying spaces were present between the stria. On a three-dimensional basis, the best analogy is the layering of an onion. One photograph was digitized giving good quantification of the sizes of the layers and their number. Similar, but less easily resolved, lens cortex organization has been described frequently in humans as "zones of optical discontinuity." These have been explained as a periodic temporal consequence of normal aging with layer thickness depending on general health. We found that young cetaceans have few "zones" and older cetaceans have many. Lens zones measurement may be developed to Provide objective data on history of cetacean health and age.     

Hominid brain size versus time: Revised regression estimates

This paper represents a revision of the regression estimates proposed in an earlier version (Journal of Human Evolution 1973 2, 405–411). An attempt has been made to incorporate new fossil material and the increasing number of absolute dates. The results of this new analysis suggest that the trend in the relationship of hominid cranial capacity with time remains consistent but the regression parameters have changed.