The phrase "already distinct" is correct and usable in written English.
It can be used to describe something that is clearly different or separate from something else at a previous point in time.
Example: "The two species were already distinct before the environmental changes occurred."
Alternatives: "previously separate" or "already differentiated".
The researchers conclude that the platypus and echidna branches of monotremes were already distinct at that early date.
Ali had a superb ninth round, drawing traces of blood around Frazier's nose and mouth and adding to the already distinct swellings around the eyes.
But the lineages leading to different modern orders of mammals were already distinct".
These two populations began evolving independently as early as 800,000 years ago and were already distinct subspecies by the time humans harnessed them a mere 6000 years ago.
In the present study, LM was applied to dissect endosperm tissues at the early storage phase, 7 DAF, when the differentiation of aleurone layers and starchy endosperm is already distinct (Ishimaru et al. 2003) and the degree of starch accumulation varies with endosperm region (Hoshikawa 1968).
Already, distinct glycan profiles have been identified in sera from patients with ovarian, 51) breast, 52) and prostate 58) cancers using mass spectrometry profiling techniques.
Morgan, now 2, has already developed distinct video preferences.
Not yet 30, Heywood was already a distinct Whitehall presence: even younger-looking than his years, floppy-haired, skinny verging on gaunt, often speaking in a discreet murmur but intimidatingly confident, still a ferocious smoker.
Even at t = 0 min, there are already three distinct features in the PL spectrum: band-edge emission at ~360 nm, Mn emission at ~590 nm, and a broader feature at ~680 nm.
The agency has already delisted distinct groups of wolves in the Great Lakes region in 2011, and in the Northern Rocky Mountains in 2012; both populations exceeded recovery targets by an order of magnitude.
Furthermore, they suggest that quiescent UC and CD mucosa already has distinct miRNA signatures which are not associated with significant variations in cellular contexts.
