http://jhered.oxfordjournals.org/cgi/reprint/96/3/212
"Among mammals, only humans, bats, whales, and
dolphins are vocal-learning animals (Haesler et al. 2004).
Our previous study showed that whale, bat, and human do
not share any amino acid changes in exon 7 of FoxP2 (Zhang
et al. 2002). Additional sequences from vocal-learning
(dolphin) and non-vocal-learning (hippopotamus) cetartiodactyls
show that whales and dolphins share three amino acid
substitutions while their closest relative, the hippopotamus,
is identical to mouse. Notably, the human-unique substitution
(T303N) was flanked by two changes in both whale
and dolphin (S302P and T304A).
"
(after some maybe elephants too...)
"Distribution of song learning among birds used
in this study:
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1. Song learning is found in all members of the
order Psittaciformes (parrots).Budgerigar is a member of
Psittaciformes.
2. Song learning is found in all members of the
suborder Passeri (oscines). House sparrow and zebra finch are
members of Passeri.
3.a Within the order Trochiliformes
(hummingbirds), song learning has been found in a few
species (e.g., Anna's hummingbird)
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3.b but not in others (e.g.,
ruby-throated hummingbird).
4. Song learning is absent in all
members of the suborder Tyranni (suboscines). Eastern
phoebe is a member of Tyranni.
5. Song learning is absent from
all members of the order Galliformes. Chicken is a member of
Galliformes.
Songs, as opposed to calls, are usually complex,
multinoted vocalizations produced by males under hormonal
regulation during the breeding season for mate attraction and
territorial defense. Phylogenetic relationships follow Sibley and
Ahlquist (1990).
"
"
Although WE DID NOT FIND PARALLEL AMINO ACID CHANGES
BETWEEN HUMANS AND OTHER VOCAL-LEARNING ANIMALS, the study
of FoxP2 in nonhuman vocal learners is only beginning.
There is now tantalizing evidence of differential FoxP2
expression in song-associated brain regions during periods of
song remodeling in zebra finches (Haesler et al. 2004; but see
Teramitsu et al. 2004), and the extreme sequence conservation
in FoxP2 remains to be explained.
THE MOLECULAR FUNCTION OF THE HUMAN UNIQUE SUBSTITUTION IS YET TO BE DETERMINED and it will be interesting to compare the
conserved and altered roles of FoxP2 in various mammals
and birds of vocal learners and nonlearners."