Do Nectar- and Fruit-Eating Birds Have Lower Nitrogen Requirements Than Omnivores? an Allometric TestAuk
AbstractWe used an allometric approach to compare the minimum nitrogen requirements (MNR) and the total endogenous nitrogen loss (TENL) of nectar- and fruit-eating birds with those of omnivorous birds. These two parameters were 4x higher in omnivores than in nectarivores and frugivores. In nectarivorous-frugivorous birds, MNR was 152.8 mg N kg(-0.76) day(-1); in omnivorous birds, it was 575.4 mg N kg(-0.76) day(-1). Similarly, TENL was 54.1 mg N kg(-0.69) day(-1) in nectarivores-frugivores, and 215.3 mg N kg(-0.69) day(-1) in omnivores. The residuals of the allometric relationships between TENL and MNR and body mass were positively correlated, which suggests that a large proportion of the interspecific variation in MNR is explained by variation in TENL. Although our results show that nectar- and fruit-eating birds have low nitrogen requirements, the mechanisms that these animals use to conserve nitrogen remain unclear.
Citation InformationE. Tsahar, Z. Ara, I. Izhaki and Carlos Martinez del Rio. "Do Nectar- and Fruit-Eating Birds Have Lower Nitrogen Requirements Than Omnivores? an Allometric Test" Auk Vol. 123 Iss. 4 (2006) p. 1004 - 1012
Available at: http://works.bepress.com/carlos_delrio/2/