Marsupial joeys are born ectothermic and develop endothermy within their mother's thermally stable pouch. We hypothesized that Tammar wallaby joeys would switch from α-stat to pH-stat regulation during the transition from ectothermy to endothermy. To address this, we compared ventilation (Ve), metabolic rate (Vo2), and variables relevant to blood gas and acid-base regulation and oxygen transpor...

We investigated thoracic temperatures (Tth) during different activities of the endothermic fruit beetle Pachnoda sinuata and analysed which energy substrates are used for the pre-flight warm-up of its flight muscles. Pachnoda sinuata elevates its Tth prior to take-off either by basking in the sun or by warming endothermically to a narrow range around 34 degreesC. During lift-generating tethered...

Emulsified high-density amorphous ice, made by pressure-induced amorphization of emulsified ice Ih, was decompressed at about 160 K. The onset of an endothermic event was observed around 0.4 GPa during the decompression. This is consistent with existence of the glass transition to a liquid state, implying the close relationship between melting and amorphization.

A soluble delipidized (Na + K)-stimulated ATPase was obtained from rabbit kidney outer medulla by the use of sodium deoxycholate. The activity of this enzyme was stimulated ZO-fold to an activity of 100 to 120 pmoles of Pi per mg of protein per hour by either phosphatidylserine or phosphatidylglycerol. The effect of the fluidity of the hydrocarbon region of the phospholipid bilayers on this re-...

The embryonic modal value of heart rate (MHR) differs between broiler and White Leghorn chickens, but the initial development of cholinergic chronotropic control of embryonic heart rate (HR) does not. Thus, we hypothesized that hatchling MHR should also differ between broiler and White Leghorn strains, while the development of a physiological regulation, such as the endothermic HR response, sho...

Cyclocephala colasi beetles are facultative endotherms that spend most of their adult lives inside the inflorescences of Philodendron solimoesense, where ambient temperature (T(a)) averages about 28 degrees C due to floral thermogenesis. Measurements of respiration within a range of T(a) showed that active beetles became spontaneously endothermic at T(a) below 28 degrees C but were rarely endot...

Parental care meets several critical needs of developing offspring. In particular, egg brooding in pythons is an exceptional model for examining environmental influences on specific parental behaviors because brooding behaviors are dynamic yet simple and modulate embryonic temperature, respiration, and water balance. We used captive Children's pythons (Antaresia childreni) to assess their facul...