11. Thermogenic herbs, for example, can cause problems for individuals with hypertension or cardiac problems,12. Newman has advanced a novel scenario for the origin of birds, the Thermogenic Muscle Hypothesis. 13. Consisting of mostly methane, natural gas is produced using two methods : biogenic and thermogenic . 14. Their thermogenic properties cause an increase in metabolism, as evidenced by an increase in body heat. 15. Isotopic data from wells in the Zonguldak basin suggest that the methane is primarily thermogenic in nature. 16. Also in the pipeline are so-called thermogenic drugs that act as stimulants, boosting energy expenditure. 17. Deeper in the earth, at greater temperature and pressure, thermogenic gas is created from buried organic material. 18. One of a rare group of thermogenic plants, the dead horse arum can raise its temperature by thermogenesis. 19. The report further states the gas was microbial in origin and not thermogenic like gas produced from gas wells. 20. It has thermogenic and anorectic effects in animal studies, making it potentially useful for the treatment of obesity.