The consideration of iron effects on marine ecosystems has focused mainly on high-nitrate low-chlorophyll regions, but iron likely has an equally important regulatory role in coastal waters. Iron requirements of neritic phytoplankton not only are comparatively high but also differ substantially among species, so that iron fluctuations within metal-replete systems should strongly influence the c...

The Princeton Project on the Decline of Fertility in Europe (or European Fertility Project, hereafter EFP) was carried out at Princeton University’s Office of Population Research in the 1960s and 1970s. This project aimed to characterize the decline of fertility that took place in Europe during the nineteenth and early twentieth centuries. The project’s summary statements argued that social and...

We examined the bioavailability of iron-storage proteins—including representatives of maxiand miniferritins—to various species of marine phytoplankton. Both eukaryotic and prokaryotic species were able to grow rapidly with horse spleen ferritin (HoSF) or deoxyribonucleic acid (DNA)-binding proteins from starved cells (Dps) from Trichodesmium erythraeum as the sole Fe source in the medium. In th...

We have discovered that coastal and oceanic diatoms require more manganese (Mn) to grow in iron (Fe) -deficient than in Fe-sufficient seawater. At low inorganic concentrations, like those of the open sea, Fe and Mn can thus colimit Thalassiosira pseudonana and T. oceanica so that maximum rates of cell division are achieved only when both resources are added simultaneously to cultures. Colimited...

Thanks to substantial improvements in child and adult survival through most parts of the world in the last decades, old‐age mortality accounts now for large fractions of death. Yet for many developing countries, old‐age mortality is often only inferred by model life tables using mortality data at young ages, or sometimes at young and adult ages; and reliable estimates of old‐age mortality using...

—Results of queries through public avian list-servers and a thorough literature search formed a data base to synthesize patterns of birds trapped in spider webs. Sixty-nine cases of birds, representing 54 species in 23 families, were reported trapped in webs. Hummingbirds were the most diverse family (nine species) and had the most cases of entrapment (n 5 20). Archilochus colubris represented ...

Most studies of the organic complexation of Cu in natural waters have focused on distributions and processes in the water column, where a significant fraction of Cu-complexing ligands may be biologically produced. We present direct evidence for a flux of Cu-complexing ligands from estuarine sediments, demonstrating that sediments are a significant, yet previously unrecognized source of the liga...

fore be helpful to develop sugarcane cultivars that produce high yields with less P fertilizer or cultivars that Rapid screening for high leaf P concentration may help sugarcane take up more soil P. Sugarcane in the EAA obtains 30 (interspecific hybrids of Saccharum spp.) growers in the Everglades Agricultural Area reduce P in discharge water, an important compoto 85% of its total P from soil P...

Most studies of the organic complexation of Cu in natural waters have focused on distributions and processes in the water column, where a significant fraction of Cu-complexing ligands may be biologically produced. We present direct evidence for a flux of Cu-complexing ligands from estuarine sediments, demonstrating that sediments are a significant, yet previously unrecognized source of the liga...

Conventional theories have little to say about the level at which fertility will stabilize at the end of the demographic transition, although it is often assumed that replacement fertility of about 2.1 births per woman will prevail in the long run. However, fertility has dropped below the replacement level in virtually every population that has moved through the transition. If future fertility ...