Errata
ECOLOGY, FOURTH EDITION
Robert E. Ricklefs and Gary L. Miller
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CORRECTIONS ARE IN BOLD.
Insects eating food (%)
PAGE 127: Figure 7-16.
The diagram for the oldest juveniles should look like the diagram below.
50
0
Agrostis
Festuca
Oldest juveniles
(gape size 0.25mm)
PAGE 235: second column, first full paragraph, last sentence.
Endomycorrhizae are the most common form
found in the Tropics (Janos 1980).
PAGE 236: first column, first full paragraph, first sentence.
(Carroll and Wicklow).
PAGE 284: second column, third paragraph, third sentence.
The area of a circle with radius r is πr2, so the area of a
circle having radius r=2s is π(2s)2, or 4πs2.
PAGE 305: bottom of first column.
So, the following multiplications may be performed:
4
[1 2 3] X 5 
 
6 
1X3
1 2 3
[1 2 3] X 4 5 6
7 8 9
3X1
1X3
3X3
but the following could not be:
1  1 2 3
 2  X  4 5 6

  
3  7 8 9
1   4 
 2  X 5 
   
3  6 
3X1 3X1
1X3
3X3
The order of the matrix that results from a multiplication of two matrices is the number of
rows of the first matrix and the number of columns of the second, as shown below:
1 2 3
[1 2 3] X 4 5 6 = [a b c]
7 8 9
1X3
3X3
1X3
Now, how do we find the elements of the 1 X 3 matrix resulting from the above
multiplication? That is, how, precisely, is the multiplication accomplished? The
multiplication results from a series of steps in which each element of the row vector is
multiplied with the corresponding element of a column of the matrix and those results are
summed. This operation is repeated for each of the three columns of the matrix to obtain
each element of the new matrix. For example, to get the first element, a, of the matrix
above, we first multiply the first element of the row vector, 1, by the first member of the
first column of the matrix, 1. Then we multiply the second element of the vector, 2, by
the second element of the first column of the matrix, 4, to obtain 2 X 4 = 8. This result is
added to the first multiplication. Finally, we multiply the third, last, element of the vector
by the third element of the first column of the matrix, 7, to obtain 3 X 7 = 21, and this is
added to the results of the other two operations. Thus, the operations performed to obtain
the first element of the vector that results from the multiplication are summarized as: (1 X
1) + (2 X 4) + (3 X 7) = 1 + 8 + 21 = 30. The complete set of operations is shown below:
1 2 3
 (1)(1)  (2)( 4)  (3)(7)


[1 2 3] X 4 5 6 = (1)( 2)  (2)(5)  (3)(8)  = [30 36 42]
7 8 9
 (1)(3)  (2)(6)  (3)(9) 
PAGE 416: Figure 21-12
The labels for the vectors Cj and Ci should be switched.
PAGE 476: second column, first paragraph, second to last sentence.
M = (a - c)/b NOT M = (c - a)/b