Assumption:

Tertiary wing feathers are warmer

Hypotheses:

1) During cold weather feather mites will accumulate on the tertiary wing feather

2) During warm weather feather mites will spread evenly over the entire wing

In winter 2010-11 and summer 2011 I took exact counts of feather mites for each individual wing feather (primaries: p1-p10, secondaries: s1-s6, and tertiaries: t1-t3) of blue tits. And, looking at the data, I can see with the naked eye that in winter most mites are accumulated on the tertiary feathers and during summer they are spread all over the wing. However, so far I've been unable to employ the right statistical test to back those findings. The data is

Kruskal-Wallis Test on Winter Mite Count

Winter

Remiges_____N__Median____Ave Rank____Z

Win Prim____48_2.000_____61.7______-2.20

Win Sec_____48_5.500_____78.1_______1.15

Win Tert____48_7.000_____77.7_______1.05

Overall_____144__________72.5

H = 4.83 DF = 2 P = 0.089

H = 4.92 DF = 2 P = 0.085 (adjusted for ties)

Kruskal-Wallis Test on Summer Mite Count

Summer

Remiges_____N_______Median____Ave Rank____Z

Sum Prim____44______4.5000____90.2_______5.03

Sum Sec_____44______1.0000____63.7______-0.60

Sum Tert____44______0.0000____45.6______-4.43

Overall_____132_______________66.5

H = 30.17 DF = 2 P = 0.000

H = 33.07 DF = 2 P = 0.000 (adjusted for ties)

Although this gives me a P-value for winter (P>0.05) confirming that there is a difference and a P-value for summer (P<0.001) for no difference, which is exactly what I wanted, I believe that there is an overall difference between the three kinds of remiges, but how can I compare primaries and secondaries with tertiaries? Or does this already show what I need?

If there is a way to attach my data (.xls) to this post, please let me know, I'll gladly do so. The upload manager doesn't seem to except my .xls

This is a direct download link for the data from mobileMe.com:

https://files.me.com/xavierschmit/5vqcw9

Any help would be greatly appreciated as I'm running out of time,

Cheers,

aXe

Tertiary wing feathers are warmer

Hypotheses:

1) During cold weather feather mites will accumulate on the tertiary wing feather

2) During warm weather feather mites will spread evenly over the entire wing

In winter 2010-11 and summer 2011 I took exact counts of feather mites for each individual wing feather (primaries: p1-p10, secondaries: s1-s6, and tertiaries: t1-t3) of blue tits. And, looking at the data, I can see with the naked eye that in winter most mites are accumulated on the tertiary feathers and during summer they are spread all over the wing. However, so far I've been unable to employ the right statistical test to back those findings. The data is

**not**normally distributed, the variances are**not**homogenous and the sample size is**greater than 20**, hence I tried using the Kruskal-Wallis test (Dytham 2011). The results from Minitab 15 are as follows:**Kruskal-Wallis Test: Winter Mite Count versus Winter Remiges**Kruskal-Wallis Test on Winter Mite Count

Winter

Remiges_____N__Median____Ave Rank____Z

Win Prim____48_2.000_____61.7______-2.20

Win Sec_____48_5.500_____78.1_______1.15

Win Tert____48_7.000_____77.7_______1.05

Overall_____144__________72.5

H = 4.83 DF = 2 P = 0.089

H = 4.92 DF = 2 P = 0.085 (adjusted for ties)

**Kruskal-Wallis Test: Summer Mite Count versus Summer Remiges**Kruskal-Wallis Test on Summer Mite Count

Summer

Remiges_____N_______Median____Ave Rank____Z

Sum Prim____44______4.5000____90.2_______5.03

Sum Sec_____44______1.0000____63.7______-0.60

Sum Tert____44______0.0000____45.6______-4.43

Overall_____132_______________66.5

H = 30.17 DF = 2 P = 0.000

H = 33.07 DF = 2 P = 0.000 (adjusted for ties)

Although this gives me a P-value for winter (P>0.05) confirming that there is a difference and a P-value for summer (P<0.001) for no difference, which is exactly what I wanted, I believe that there is an overall difference between the three kinds of remiges, but how can I compare primaries and secondaries with tertiaries? Or does this already show what I need?

If there is a way to attach my data (.xls) to this post, please let me know, I'll gladly do so. The upload manager doesn't seem to except my .xls

*(500(IOErrorEvent type="ioError"bubbles=false cancelable=false eventPhase=2text="Error #2038")*)This is a direct download link for the data from mobileMe.com:

https://files.me.com/xavierschmit/5vqcw9

*Please note: summer and winter data in separate work sheets in same document*Any help would be greatly appreciated as I'm running out of time,

Cheers,

aXe

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