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SPECIES FOR WHICH ORTHOLOGOUS EXONS ARE AVAILABLE

EUARCHONTOGLIRES
Homo_sapiensHumanv1
Pan_troglodytesChimpv1
Macaca_mulattaMacaquev1
Otolemur_garnettiiBushbabyv2
Microcebus_murinusMouse lemurv2
Tupaia_belangeriTree shrewv2
Mus_musculusMousev1
Rattus_norvegicusRatv1
Cavia_porcellusGuinea pigv2
Spermophilus_tridecemlineatusGround squirrelv2
Oryctolagus_cuniculusRabbitv1
Ochotona_princepsPikav2
LAURASIATHERIA
Bos_taurus Cowv1
Canis_familiarisDogv1
Felis_catusCatv2
Myotis_lucifugusMicrobatv2
Erinaceus_europaeusHedgehogv2
Sorex_araneusShrewv2
AFROTHERIA
Loxodonta_africanaElephantv1
Echinops_telfairiTenrecv1
XENARTHRA
Dasypus_novemcinctusArmadillov1
MARSUPIALIA
Monodelphis_domesticaOpossumv1
MONOTREMATA
Ornithorhynchus_anatinusPlatypus
v2




OrthoMaM exons are selected for a minimum of 6 species and a maximum of 23 species.

OrthoMaM mean = 14 ; standard-error = 3


RELATIVE EVOLUTIONARY RATE
The utility of a phylogenetic marker can be described by its relative evolutionary rate:
faster (respectively slower) evolving markers will be more suitable
for lower (respectively deeper) taxonomic levels.

In a first approximation, the total branch length (TBL) of the highest-likelihood tree
is a reasonable descriptor of the evolutionary rate of a given exon.
However, the TBL will preclude fair comparisons among different exons
when the taxon sampling differs: the higher the species number, the longer the TBL.

To circumvent this problem, we use the Super Distance Matrix (SDM) approach [Criscuolo et al. 2006],
with a three-step procedure:

(i) The ML tree inferred from each of the 4,155 exons is converted
into a matrix of additive distances by computing the path-length
between each pair of species.
(ii) Each of the 4,155 matrices is brought closer to the others by a factor (αp),
according to the least-squares criterion.
This operation is equivalent to multiplying by αp every branch length
of the initial trees.
(iii) Optimal values of the alpha_p parameters are calculated following Criscuolo et al. (2006),
As αp are inversely proportional to the evolutionary rates,
1/αp values provide a measure of rate heterogeneities among exons
even if the number of taxa differs.

Exon-specific evolutionary rates are provided as relative values ranging from 0 to 2.8.

For example, if exons X and Y are respectively characterized by relative rates
rX = 0.2 and rY = 2.0, this means that Y is evolving 10 times faster than X.

Relative evolutionary rate SDM estimates here range from 0.02 to 2.8
OrthoMaM mean = 1.4 ; standard-error = 0.7

Reference: Criscuolo A., Berry V., Douzery E. J. P. & Gascuel O., 2006.
SDM: a fast distance-based approach for (super)tree building in phylogenomics.
Systematic Biology 55 (5) : 740-755.
α SHAPE OF THE Γ DISTRIBUTION
The substitution rate heterogeneity among sites of the exon alignment
is described by the Γ distribution.

Lower (respectively higher) α values correspond to strong (respectively weak)
heterogeneity. If α > 1, the substitution pattern among sites is rather homogeneous.

α estimates here range from 0.01 to 5.0.
OrthoMaM mean = 0.6 ; standard-error = 0.6

Reference: Yang Z., 1996.
Among-site rate variation and its impact on phylogenetic analyses.
Trends in Ecology and Evolutin 11 (9) : 367-372.

PERCENTAGE OF G+C ON THIRD CODON POSITIONS
This parameter is a descriptor of the degree of base composition heterogeneity.
It is more contrasted on third codon positions than on the whole exon.

%GC3 estimates here range from 22% to 96%
OrthoMaM mean = 66% ; standard-error = 15%