predicted here. For example, adult Gala ́pagos fur seal femalesArctocephalus
galapagoensisaverage about 28 kg in body mass (Horning & Trillmich, 1997 ).
Gala ́pagos fur seal bulls average about 70 kg in body mass (http://www.tamug.
tamu.edu/labb/Galapagos/GFSwork/GFS_work.htm, accessed 27 August 2005).
Cohenet al.(2003), Reuman and Cohen ( 2004 ), Jonsson, Cohen and Carpenter
(2005), Reuman and Cohen ( 2005 ), and Cohen and Carpenter (2005) analyzed the
community food web, the numerical abundance and the average body size of
species in the pelagic community of a small lake, Tuesday Lake, in Michigan.
The raw data on the food web, average body mass and numerical abundance by
(^1010) −14 10 −12 10 −10 10 −8 10 −6 10 −4 10 −2
−14
10 −12
10 −10
10 −8
10 −6
10 −4
10 −2
prey body mass (kg)
predator body mass (kg)
(b)
10 −14 10 −12 10 −10 10 −8 10 −6 10 −4 10 −2 100
100
prey body mass (kg)
(c)
10 −14
10 −12
10 −10
10 −8
10 −6
10 −4
10 −2
predator body mass (kg)
Figure 16.2(cont.)
BODY SIZES IN FOOD CHAINS 315