15 research outputs found
African Rice (Oryza glaberrima Steud.): Lost Crop of the Enslaved Africans Discovered in Suriname1
African Rice (Oryza glaberrimaSteud.): Lost Crop of the Enslaved Africans Discovered in Suriname. African rice (Oryza glaberrima Steud.) was introduced to the Americas during the slave trade years and grown by enslaved Africans for decades before mechanical milling devices facilitated the shift towards Asian rice (O. sativa L.). Literature suggests that African rice is still grown in Guyana and French Guiana, but the most recent herbarium voucher dates from 1938. In this paper, evidence is presented that O. glaberrima is still grown by Saramaccan Maroons both for food and ritual uses. Saramaccan informants claim their forefathers collected their first “black rice” from a mysterious wild rice swamp and cultivated these seeds afterwards. Unmilled spikelets (grains with their husk still attached) are sold in small quantities for ancestor offerings, and even exported to the Netherlands to be used by Maroon immigrants. Little is known of the evolution of O. glaberrima, before and after domestication. Therefore, more research is needed on the different varieties of rice and other “lost crops” grown by these descendants of enslaved Africans who escaped from plantations in the 17th and 18th centuries and maintained much of their African cultural heritage in the deep rainforest
Reproductive abnormalities in mice expressing omega-3 fatty acid desaturase in their mammary glands
The Caenorhabditis elegans n-3 fatty acid desaturase (Fat-1) acts on a range of 18- and 20-carbon n-6 fatty acid substrates. Transgenic female mice expressing the Fat-1 gene under transcriptional control of the goat β-casein promoter produce milk phospholipids having elevated levels of n-3 polyunsaturated fatty acids (PUFA). However, females from this line were also observed to have impaired reproductive performance characterized by a smaller litter size (2.7 ± 0.6 vs. 7.2 ± 0.7; P < 0.05) than wildtype controls. While there is a close association between PUFA metabolism, prostaglandin biosynthesis, and fertility; reproductive problems in these mice were unanticipated given that the Fat-1 transgene is primarily expressed in the lactating mammary gland. Using multiple approaches it was found that Fat-1 mice have normal ovulation and fertilization rates; however fewer embryos were present in the uterus prior to implantation. Small litter size was also found to be partly attributable to a high incidence of post-implantation fetal resorptions. Embryo transfer experiments revealed that embryos developing from oocytes derived from transgenic ovaries had an increased rate of post-implantation resorption, regardless of the uterine genotype. Ovary transplantation between Fat-1 and C57BL/6 wildtype females revealed that non-ovarian factors also contributed to the smaller litter size phenotype. Finally, surgical removal of the mammary glands from juvenile Fat-1 mice increased the subsequent number of implantation sites per female, but did not lessen the high rate of post-implantation resorptions. In conclusion, we herein report on a system where an exogenous transgene expressed predominately in the mammary gland detrimentally affects female reproduction, suggesting that in certain circumstances the mammary gland may function as an endocrine regulator of reproductive performance
Biologically active substances-enriched diet regulates gonadotrope cell activation pathway in liver of adult and old rats
The use of Amerindian charm plants in the Guianas
Background: Magical charm plants to ensure good luck in hunting, fishing, agriculture, love and warfare are known among many Amerindians groups in the Guianas. Documented by anthropologists as social and political markers and exchangeable commodities, these charms have received little attention by ethnobotanists, as they are surrounded by secrecy and are difficult to identify. We compared the use of charm species among indigenous groups in the Guianas to see whether similarity in charm species was related to geographical or cultural proximity. We hypothesized that cultivated plants were more widely shared than wild ones and that charms with underground bulbs were more widely used than those without such organs, as vegetatively propagated plants would facilitate transfer of charm knowledge. Methods: We compiled a list of charm plants from recent fieldwork and supplemented these with information from herbarium collections, historic and recent literature among 11 ethnic groups in the Guianas. To assess similarity in plant use among these groups, we performed a Detrended Component Analysis (DCA) on species level. To see whether cultivated plants or vegetatively propagated species were more widely shared among ethnic groups than wild species or plants without rhizomes, tubers or stem-rooting capacity, we used an independent sample t-test. Results: We recorded 366 charms, representing 145 species. The majority were hunting charms, wild plants, propagated via underground bulbs and grown in villages. Our data suggest that similarity in charm species is associated with geographical proximity and not cultural relatedness. The most widely shared species, used by all Amerindian groups, is Caladium bicolor. The tubers of this plant facilitate easy transport and its natural variability allows for associations with a diversity of game animals. Human selection on shape, size and color of plants through clonal reproduction has ensured the continuity of morphological traits and their correlation with animal features. Conclusions: Charm plants serve as vehicles for traditional knowledge on animal behavior, tribal warfare and other aspects of oral history and should therefore deserve more scientific and societal attention, especially because there are indications that traditional knowledge on charms is disappearing