Overland to the island [poem analysis]

Overland to the island
by Denise Levertov

Let’s go – much as that dog does,
intently haphazard. The
Mexican light on a day that
‘smells like autumn in Connecticut’
makes iris ripples on his
black gleaming fur – and that too
is as one would desire – a radiance
consorting with the dance.
-----------Under his feet
rocks and mud, his imagination, sniffing,
engaged in its perceptions – dancing
edgeways, there’s nothing
the dog disdains on his way,
nevertheless he
keeps moving, changing
pace and approach but
not direction – ‘every step an arrival.’

Words definition:

Overland: (adv) By way of land.

Haphazard: (adv) By chance; casually.

Connecticut: A state of the northeast United States.

Ripples: ripple (v) To cause to form small waves or undulations.

Gleaming: gleam (v) To emit a gleam; flash or glow.

Consorting: consort (v) To escort; accompany.

Edgeways: edgeway (adv) On, by, with, or toward the edge.

Disdains: disdain (v) to refuse or reject with a feeling or show of superiority and dislike.

Pace: (v) The rate of speed at which a person, animal, or group walks or runs.

I don't get this. And there is no critic or explanation found on Google.
What is the relation with dog and Mexican?