Petroleum and natural gas are the primary fuels in the US food system. Both fuels are now in short supply and significant quantities are being imported into the USA from various nations. An investigation documented that fossil energy use in the food system could be reduced by about 50% by appropriate technology changes in food production, processing, packaging, transportation, and consumption. The results suggest that overall, farmers benefit as well as consumers.

Turtle embryos enter a state of arrested development in the oviduct, allowing the mother greater flexibility in her reproductive schedule. Development recommences once eggs transition from the hypoxic oviduct to the normoxic nest. Significant mortality can occur if turtle eggs are moved between 12 h and 20 d after oviposition, and this is linked to the recommencement of embryonic development. To better understand the timing of developmental arrest and to determine how movement-induced mortality might be avoided, we determined the latency (i.e., time elapsed since oviposition) to recommencement of development following oviposition by exposing the eggs of green turtles (Chelonia mydas) to hypoxia (oxygen tension <8 mmHg) for 3 d, commencing 30 min to 48 h after oviposition. Embryonic development-including development of the characteristic opaque white spot on the eggshell-was halted by hypoxic incubation. When the delay before hypoxic incubation was 12 h or less, hatching success did not differ from a control group. If the hypoxic treatment began after 16 h or more in normoxia, then all embryos died. Thus, by returning eggs to a hypoxic environment before they have broken from arrest (i.e., within 12 h of oviposition), it is possible to extend embryonic arrest for at least 3 d, with no apparent detriment to hatching success. Therefore, hypoxic incubation may provide a new approach for avoidance of movement-induced mortality when conservation or research efforts require the relocation of eggs. Our findings also suggest that movement-induced mortality may have constrained the evolution of viviparity in turtles.

Summary An analysis is described using heritability estimates for racing performance in the Australian Thoroughbred, calculated using the complete race results of two recent years. A number of methods, some new, for assessing racing performance were used. The results confirm that heritability for racing performance is high, with the estimates ranging to above 0.6. This value is somewhat higher than that obtained in overseas studies, although when the same measures are analysed, the estimates found are comparable. Rather than just dismissing these estimates as too high, a number of factors which may affect their size, both upwards and downwards, are discussed. The conclusions reached are that high estimates are probably real and are compatible with a constantly selected population if the selection practised is not accurate. Furthermore, the danger (or folly) of striving to lower the estimates obtained by the utilization of more sophisticated statistical processes, without proper consideration for the biological nature of the characters being studied, nor indeed their precise definition, is highlighted. Zusammenfassung Hentabilität von Rennerfolg in Vollblütern: Eine Analyse australischer Daten Anhand von den gesammten Daten über Ergebnisse von Galopprennen in ganz Australien in zwei der letzten Jahren wurde Heritabilität von Rennerfolg geschätzt. Verschiedene Methoden den Rennerfolg zu messen wurden benützt, darunter auch neue. Die Analyse bestätigt daß Heritabilität von Rennerfolg hoch ist, einige Schätzwerte liegen über 0.6. Diese Werte sind etwas höher als übliche Werte in der Literatur, aber wo die gleichen Messmethoden benützt wurden sind unsere Werte mit denen der Literatur vergleichbar. Ohne diese Schätzwerte als zu hoch abzuwerten, diskutieren wir Faktoren welche Schätzwerte in ihrer Größe beeinflussen können, nach oben wie nach unten. Wir ziehen den Schluß, daß hohe Schätzwerte für Heritabilität von Rennerfolg wahrscheinlich den richtigen Sachverhalt darstellen. Dieser ist mit einer Population unter ständigem Selektionsdruck vereinbar wenn die Selektion nicht akkurat ist. Weiterhin wird die Gefahr beleuchtet, die in Versuchen besteht, Schätzwerte der Heritabität durch sophistische statistische Methoden zu mindern, wenn man die eigentlichen biologischen Sachverhalte der analysierten Merkmale nur ungenau kennt.

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