Re: [R-sig-phylo] variation in rates over time

2012-09-17 Thread Brian O'Meara
I agree with the suggestions so far. I just wanted to point out a few more
alternatives:

You could use the geiger package to estimate the best scaling for the
tworatetree transformation to do this (should be equivalent to the earlier
solutions, though it would require running optimization).

You could also use the OUwie package with a tree that has been given simmap
mappings using phytools. The advantage of this is that you could evaluate
Brownian models but you could also look at various Ornstein-Uhlenbeck
models (though note that while there is information about different
Brownian rates before and after a time slice, info about different alphas
(strength of pull parameter) and thetas (the attractor, aka "optimal
value") is rapidly (but not immediately) lost under an OU process).

For completeness, especially for citations, note that O'Meara et al. (2006)
and Thomas et al. (2006) independently arrived at essentially the same
method, so it is worth reading both papers.

Best,
Brian

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On Mon, Sep 17, 2012 at 9:11 PM, Jason S  wrote:

>
>
> Thanks, guys. That's exactly what I needed.
>
>
> 
>  From: Liam J. Revell 
> To: Matt Pennell 
>
> -project.org>
> Sent: Monday, September 17, 2012 9:22 PM
> Subject: Re: [R-sig-phylo] variation in rates over time
>
> Hi Jason. Matt is absolutely correct. You can do this with phytools.
> Say, for instance, you have an ultrametric phylogeny with branches in
> millions of years (tree) and data vector containing the trait values for
> species (x) and you want to test the hypothesis that the last 3.4 my has
> a different rate of evolution than the rest of the tree, you could do
> this as follows:
>
> library(phytools) # load phytools
> tree<-make.era.map(tree,c(0,max(nodeHeights(tree))-3.4))
> plotSimmap(tree,pts=F,lwd=3) # visualize
> fit<-brownie.lite(tree,x) # fit model
>
> That's it. Good luck. Liam
>
> Liam J. Revell, Assistant Professor of Biology
> University of Massachusetts Boston
> web: http://faculty.umb.edu/liam.revell/
> email: liam.rev...@umb.edu
> blog: http://phytools.blogspot.com
>
> On 9/17/2012 7:46 PM, Matt Pennell wrote:
> >
>  Jason,
> >
> > I think the best way to do this is with the approach of O'Meara et al.
> 2006
> > Evolution "Brownie".
> >
> > Liam Revell has implemented this in R in his package phytools. You can
> > modify the steps taken in this tutorial here
> >
> http://phytools.blogspot.com/2011/07/running-brownielite-for-arbitrarily.html
> > perhaps
> > in conjunction with the function make.era.map()
> >
> http://phytools.blogspot.com/2011/10/new-function-to-plot-eras-on-tree.html
> > though
> > I admittedly have not tried this myself.
> >
> > Perhaps Liam or someone else has a better explanation but I hope this is
> at
> > least somewhat helpful.
> >
> > cheers,
> > matt
> >
>
> >
> >>
> >>
> >>
>  Hello,
> >>
> >> I see that there are several interesting alternatives to test for
> >> different rates among clades. However, I was wondering if there is a
> method
> >> to test for varying rates over time. I'm aware of Pagel's delta and the
> EB
> >> model, but I was thinking more in terms of testing if there is a
> different
> >> rate for the entire tree after a specified point in time. For instance,
> if
> >> a snail predator colonizes an island 3.4 Mya, is there evidence for an
> >> increased rate of evolution in the prey after that point in time?
> Something
> >> like two lambdas, one for before and one for after that point in time.
> >>
> >> Thanks!
> >>
> >> Jason
> >>  [[alternative HTML version deleted]]
> >>
> >> ___
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> >> R-sig-phylo@r-project.org
> >> https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
> >>
> >
> > [[alternative HTML version deleted]]
> >
> > ___
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> >
> [[alternative HTML version deleted]]
>
>
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>
>

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Re: [R-sig-phylo] variation in rates over time

2012-09-17 Thread Jason S


Thanks, guys. That's exactly what I needed. 



 From: Liam J. Revell 
To: Matt Pennell  

-project.org> 
Sent: Monday, September 17, 2012 9:22 PM
Subject: Re: [R-sig-phylo] variation in rates over time

Hi Jason. Matt is absolutely correct. You can do this with phytools. 
Say, for instance, you have an ultrametric phylogeny with branches in 
millions of years (tree) and data vector containing the trait values for 
species (x) and you want to test the hypothesis that the last 3.4 my has 
a different rate of evolution than the rest of the tree, you could do 
this as follows:

library(phytools) # load phytools
tree<-make.era.map(tree,c(0,max(nodeHeights(tree))-3.4))
plotSimmap(tree,pts=F,lwd=3) # visualize
fit<-brownie.lite(tree,x) # fit model

That's it. Good luck. Liam

Liam J. Revell, Assistant Professor of Biology
University of Massachusetts Boston
web: http://faculty.umb.edu/liam.revell/
email: liam.rev...@umb.edu
blog: http://phytools.blogspot.com

On 9/17/2012 7:46 PM, Matt Pennell wrote:
>
 Jason,
>
> I think the best way to do this is with the approach of O'Meara et al. 2006
> Evolution "Brownie".
>
> Liam Revell has implemented this in R in his package phytools. You can
> modify the steps taken in this tutorial here
> http://phytools.blogspot.com/2011/07/running-brownielite-for-arbitrarily.html
> perhaps
> in conjunction with the function make.era.map()
> http://phytools.blogspot.com/2011/10/new-function-to-plot-eras-on-tree.html
> though
> I admittedly have not tried this myself.
>
> Perhaps Liam or someone else has a better explanation but I hope this is at
> least somewhat helpful.
>
> cheers,
> matt
>

>
>>
>>
>>
 Hello,
>>
>> I see that there are several interesting alternatives to test for
>> different rates among clades. However, I was wondering if there is a method
>> to test for varying rates over time. I'm aware of Pagel's delta and the EB
>> model, but I was thinking more in terms of testing if there is a different
>> rate for the entire tree after a specified point in time. For instance, if
>> a snail predator colonizes an island 3.4 Mya, is there evidence for an
>> increased rate of evolution in the prey after that point in time? Something
>> like two lambdas, one for before and one for after that point in time.
>>
>> Thanks!
>>
>> Jason
>>          [[alternative HTML version deleted]]
>>
>> ___
>> R-sig-phylo mailing list
>> R-sig-phylo@r-project.org
>> https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
>>
>
>     [[alternative HTML version deleted]]
>
> ___
> R-sig-phylo mailing list
> R-sig-phylo@r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
>
[[alternative HTML version deleted]]

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Re: [R-sig-phylo] variation in rates over time

2012-09-17 Thread Liam J. Revell
Hi Jason. Matt is absolutely correct. You can do this with phytools. 
Say, for instance, you have an ultrametric phylogeny with branches in 
millions of years (tree) and data vector containing the trait values for 
species (x) and you want to test the hypothesis that the last 3.4 my has 
a different rate of evolution than the rest of the tree, you could do 
this as follows:


library(phytools) # load phytools
tree<-make.era.map(tree,c(0,max(nodeHeights(tree))-3.4))
plotSimmap(tree,pts=F,lwd=3) # visualize
fit<-brownie.lite(tree,x) # fit model

That's it. Good luck. Liam

Liam J. Revell, Assistant Professor of Biology
University of Massachusetts Boston
web: http://faculty.umb.edu/liam.revell/
email: liam.rev...@umb.edu
blog: http://phytools.blogspot.com

On 9/17/2012 7:46 PM, Matt Pennell wrote:

Jason,

I think the best way to do this is with the approach of O'Meara et al. 2006
Evolution "Brownie".

Liam Revell has implemented this in R in his package phytools. You can
modify the steps taken in this tutorial here
http://phytools.blogspot.com/2011/07/running-brownielite-for-arbitrarily.html
perhaps
in conjunction with the function make.era.map()
http://phytools.blogspot.com/2011/10/new-function-to-plot-eras-on-tree.html
though
I admittedly have not tried this myself.

Perhaps Liam or someone else has a better explanation but I hope this is at
least somewhat helpful.

cheers,
matt

On Mon, Sep 17, 2012 at 7:33 PM, Jason S  wrote:




Hello,

I see that there are several interesting alternatives to test for
different rates among clades. However, I was wondering if there is a method
to test for varying rates over time. I'm aware of Pagel's delta and the EB
model, but I was thinking more in terms of testing if there is a different
rate for the entire tree after a specified point in time. For instance, if
a snail predator colonizes an island 3.4 Mya, is there evidence for an
increased rate of evolution in the prey after that point in time? Something
like two lambdas, one for before and one for after that point in time.

Thanks!

Jason
 [[alternative HTML version deleted]]

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[[alternative HTML version deleted]]

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Re: [R-sig-phylo] variation in rates over time

2012-09-17 Thread Matt Pennell
Jason,

I think the best way to do this is with the approach of O'Meara et al. 2006
Evolution "Brownie".

Liam Revell has implemented this in R in his package phytools. You can
modify the steps taken in this tutorial here
http://phytools.blogspot.com/2011/07/running-brownielite-for-arbitrarily.html
perhaps
in conjunction with the function make.era.map()
http://phytools.blogspot.com/2011/10/new-function-to-plot-eras-on-tree.html
though
I admittedly have not tried this myself.

Perhaps Liam or someone else has a better explanation but I hope this is at
least somewhat helpful.

cheers,
matt

On Mon, Sep 17, 2012 at 7:33 PM, Jason S  wrote:

>
>
> Hello,
>
> I see that there are several interesting alternatives to test for
> different rates among clades. However, I was wondering if there is a method
> to test for varying rates over time. I'm aware of Pagel's delta and the EB
> model, but I was thinking more in terms of testing if there is a different
> rate for the entire tree after a specified point in time. For instance, if
> a snail predator colonizes an island 3.4 Mya, is there evidence for an
> increased rate of evolution in the prey after that point in time? Something
> like two lambdas, one for before and one for after that point in time.
>
> Thanks!
>
> Jason
> [[alternative HTML version deleted]]
>
> ___
> R-sig-phylo mailing list
> R-sig-phylo@r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
>

[[alternative HTML version deleted]]

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[R-sig-phylo] variation in rates over time

2012-09-17 Thread Jason S


Hello,

I see that there are several interesting alternatives to test for different 
rates among clades. However, I was wondering if there is a method to test for 
varying rates over time. I'm aware of Pagel's delta and the EB model, but I was 
thinking more in terms of testing if there is a different rate for the entire 
tree after a specified point in time. For instance, if a snail predator 
colonizes an island 3.4 Mya, is there evidence for an increased rate of 
evolution in the prey after that point in time? Something like two lambdas, one 
for before and one for after that point in time.

Thanks!

Jason
[[alternative HTML version deleted]]

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Re: [R-sig-phylo] alternative to Bartlett test of homogeneity of variances

2012-09-17 Thread Jason S
Thanks, Ted. I got another question, but I guess it would be best to start a 
new thread.




 From: Theodore Garland Jr 

-project.org> 
Sent: Monday, September 17, 2012 5:16 PM
Subject: RE: [R-sig-phylo] alternative to Bartlett test of homogeneity of 
variances

Several.  See these papers for starters:

Garland, T., Jr. 1992. Rate tests for phenotypic evolution using 
phylogenetically independent contrasts. Am. Nat. 140:509-519.

Garland, T., Jr., A. W. Dickerman, C. M. Janis, and J. A. Jones. 1993. 
Phylogenetic analysis of covariance by computer simulation. Systematic Biology 
42:265-292.

Hutcheon, J. M., and T. Garland, Jr. 2004. Are megabats big? Journal of 
Mammalian Evolution 11:257-276.

Collar, D. C., P. C. Wainwright, T. J. Near. 2005. Comparative analysis of 
morphological diversity: does morphological disparity evolve at the same rate 
in two lineages of centrarchid fishes. Evolution 58:1783-1794. [first use of 
method by O'Meara et al., 2006]

O'Meara, B. C., C. Ane, M. J. Sanderson, and P. C. Wainwright. 2006. Testing 
for different rates of continuous trait evolution using likelihood. Evolution 
60:922-933. [full explanation of method used by Collar et al., 2005]

Rezende, E. L., and J. A. F. Diniz-Filho. 2012. Phylogenetic analyses: 
comparing species to infer adaptations and physiological mechanisms. 
Comprehensive Physiology 2:639-674.

Cheers,
Ted

Theodore Garland, Jr.
Professor
Department of Biology
University of California, Riverside
Riverside, CA 92521
Office Phone:  (951) 827-3524
Facsimile:  (951) 827-4286 = Dept. office (not confidential)
Email:  tgarl...@ucr.edu
http://www.biology.ucr.edu/people/faculty/Garland.html
http://scholar.google.com/citations?hl=en&user=iSSbrhwJ

Experimental Evolution: Concepts, Methods, and Applications of Selection 
Experiments. 2009.
Edited by Theodore Garland, Jr. and Michael R. Rose
http://www.ucpress.edu/book.php?isbn=9780520261808
(PDFs of chapters are available from me or from the individual authors)


From: r-sig-phylo-boun...@r-project.org [r-sig-phylo-boun...@r-project.org]
Sent: Monday, September 17, 2012 1:08 PM
To: R-sig-phylo@r-project.org
Subject: [R-sig-phylo] alternative to Bartlett test of homogeneity of   
variances

Hi there,

Is there a PCM that is analogous to the Bartlett test of homogeneity of 
variances?

Thanks,

Jason Mustakas
        [[alternative HTML version deleted]]

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Re: [R-sig-phylo] alternative to Bartlett test of homogeneity of variances

2012-09-17 Thread Theodore Garland Jr
Several.  See these papers for starters:

Garland, T., Jr. 1992. Rate tests for phenotypic evolution using 
phylogenetically independent contrasts. Am. Nat. 140:509-519.

Garland, T., Jr., A. W. Dickerman, C. M. Janis, and J. A. Jones. 1993. 
Phylogenetic analysis of covariance by computer simulation. Systematic Biology 
42:265-292.

Hutcheon, J. M., and T. Garland, Jr. 2004. Are megabats big? Journal of 
Mammalian Evolution 11:257-276.

Collar, D. C., P. C. Wainwright, T. J. Near. 2005. Comparative analysis of 
morphological diversity: does morphological disparity evolve at the same rate 
in two lineages of centrarchid fishes. Evolution 58:1783-1794. [first use of 
method by O'Meara et al., 2006]

O'Meara, B. C., C. Ane, M. J. Sanderson, and P. C. Wainwright. 2006. Testing 
for different rates of continuous trait evolution using likelihood. Evolution 
60:922-933. [full explanation of method used by Collar et al., 2005]

Rezende, E. L., and J. A. F. Diniz-Filho. 2012. Phylogenetic analyses: 
comparing species to infer adaptations and physiological mechanisms. 
Comprehensive Physiology 2:639-674.

Cheers,
Ted

Theodore Garland, Jr.
Professor
Department of Biology
University of California, Riverside
Riverside, CA 92521
Office Phone:  (951) 827-3524
Facsimile:  (951) 827-4286 = Dept. office (not confidential)
Email:  tgarl...@ucr.edu
http://www.biology.ucr.edu/people/faculty/Garland.html
http://scholar.google.com/citations?hl=en&user=iSSbrhwJ

Experimental Evolution: Concepts, Methods, and Applications of Selection 
Experiments. 2009.
Edited by Theodore Garland, Jr. and Michael R. Rose
http://www.ucpress.edu/book.php?isbn=9780520261808
(PDFs of chapters are available from me or from the individual authors)


From: r-sig-phylo-boun...@r-project.org [r-sig-phylo-boun...@r-project.org] on 
behalf of Jason S [jas2...@yahoo.com]
Sent: Monday, September 17, 2012 1:08 PM
To: R-sig-phylo@r-project.org
Subject: [R-sig-phylo] alternative to Bartlett test of homogeneity of   
variances

Hi there,

Is there a PCM that is analogous to the Bartlett test of homogeneity of 
variances?

Thanks,

Jason Mustakas
[[alternative HTML version deleted]]

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[R-sig-phylo] alternative to Bartlett test of homogeneity of variances

2012-09-17 Thread Jason S


Hi there,

Is there a PCM that is analogous to the Bartlett test of homogeneity of 
variances?

Thanks,

Jason Mustakas
[[alternative HTML version deleted]]

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[R-sig-phylo] Phylogenetic quantile regression

2012-09-17 Thread Agus Camacho
Dear list,
Anybody knows if it would be possible to do a phylogenetic quantile
regression procedure in R or other software?
Im trying to model a relationship in which other factors beyond the ones
which entered in the analysis are potentially misleading the analysis
results. Quantile regression seems to deal well in such situations.
However, ive been looking through the internet but did not find a way to
implment PGLS over quantile regression. Is it even possible?
Thanks in advance.
Agus


-- 
Agustín Camacho Guerrero.
Doutorando em Zoologia.
Laboratório de Herpetologia, Departamento de Zoologia, Instituto de
Biociências, USP.
Rua do Matão, trav. 14, nº 321, Cidade Universitária,
São Paulo - SP, CEP: 05508-090, Brasil.
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