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Response to Comment on “Evolutionary<br />

Trade-Offs, Par<strong>et</strong>o Optim<strong>al</strong>ity, and the<br />

Geom<strong>et</strong>ry of Phenotype Space”<br />

Oren Shov<strong>al</strong>, 1 Hila Sheftel, 1 Guy Shinar, 1 Yuv<strong>al</strong> Hart, 1 Omer Ramote, 1 Avi Mayo, 1<br />

Erez Dekel, 1 Kathryn Kavanagh, 2 Uri Alon 1 *<br />

Edelaar raises concerns about the way we tested our theory. Our mathematic<strong>al</strong> theorem predicts<br />

that despite the high dimension<strong>al</strong>ity of trait space, trade-offs b<strong>et</strong>ween tasks lead to phenotypes<br />

in low-dimension<strong>al</strong> regions in trait space, such as lines and triangles. We address Edelaar’s<br />

questions with statistic<strong>al</strong> tests that eliminate pseudoreplication concerns, finding that our<br />

predictions remain convincingly supported.<br />

In Shov<strong>al</strong> <strong>et</strong> <strong>al</strong>. (1), we presented a theory in<br />

which trade-off b<strong>et</strong>ween tasks can lead natur<strong>al</strong><br />

selection to phenotypes that lie on simple<br />

shapes in the space of traits (morphospace). Two<br />

and three tasks lead to best-compromise phenotypes<br />

that f<strong>al</strong>l on a line and triangle, respectively.<br />

Good agreement was demonstrated in three<br />

re<strong>al</strong>ms: Escherichia coli gene expression, insect<br />

castes, and cross-species morphology.<br />

Edelaar (2) c<strong>al</strong>ls for improving the statistic<strong>al</strong><br />

test we used to compare the data to a triangle, for<br />

the case of cross-species morphology, focusing<br />

on Darwin’s finches (3). The improvement suggested<br />

is controlling for possible dependence<br />

of data points due to phylogen<strong>et</strong>ic relationships.<br />

In the other examples (gene expression and insect<br />

castes), this concern is not relevant because<br />

comparisons are within the same species or<br />

population.<br />

Here, we present improved statistic<strong>al</strong> tests<br />

that stringently take into account possible phylogen<strong>et</strong>ic<br />

dependence b<strong>et</strong>ween data points, finding<br />

that the predictions remain strongly supported.<br />

(i) Darwin’s finches’ triangle remains highly<br />

significant when testing m<strong>al</strong>es and fem<strong>al</strong>es separately.<br />

In (1), we used 135 data points that include<br />

data for m<strong>al</strong>es (n = 70) and fem<strong>al</strong>es (n =<br />

65). We used 10,000 randomizations in the triangle<br />

test to find P

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