Plantagenet-Harrison's "History of Yorkshire" gives the pedigree of the Yorkshire family starting with Odarus, Lord of Layton in the XII Century. (In the context, "Lord" does not imply peerage or nobility; simply that Odarus was Lord of the Manor). The family arms were; "Argent, a fess between six crosslets fitchee sable. Crest - issuing a mural crown proper, a pair of wings argent, each charged with a cross crosslet fitchee sable".
It is likely that most Laytons in England stemmed from this landed family and, as one would expect, the name occurs more frequently in the north of England than elsewhere. A count of the references (mainly christenings and marriages abstracted from parish registers) in the Mormon Church's Computer File Index (copy in the Society of Australian Genealogists) shows that the Layton references for all England, excluding Wales, constitute about 0.04% of all references. That is, one reference in 2,500 is to a Layton event.
However, the Yorkshire proportion is 0.30%- more than seven times the national average. Northumberland and Cambridgeshire have 0.11%, Bedfordshire has 0.09%, Durham 0.08%, Shropshire 0.06%, Surrey, which includes the parishes of Kew and Richmond, has 0.02% - below the national average. Lancashire, wherein the other hamlet of Layton lies, does not have a disproportion of Laytons and it may be that there was no family there called "of Layton". There has been a further pocket of Laytons in Norfolk since at least 1710.
The registers of the Surrey parish of Kew date from v1714, and those of Richmond from 1583, but the early part of the latter are in poor condition and have some blank periods, and are hard to decipher. Barnes registers start in 1583. In none of these can be found the christening of the first Michael Layton, who heads this family tree. But, because of the poor condition of the registers, this does not mean that he must have been christened elsewhere.
The name Michael occurs infrequently in Layton references, not often enough to differentiate one branch of the family from another. It appears among the Leightons of Sedburgh, and in the registers of Normanton in Yorkshire, there is the christening, 11.5.1634 of Mighill, son of Mighell Latonn. The registers of Downham parish, Cambridgeshire, record the christening of Michaell, son of George Laiton and Margaret, 8.10.1645. However, neither of these two dates fits the birth of the first Michael on this pedigree, probably no later than 1631.
Also, there were Laytons in the Thames district well before that time. There was a Layton juror in Putney in 1482 and a Layton in Kingston-upon-Thames in 1592. There were Laytons in the Middlesex parish of West Drayton as early as 1549.
What seems more likely is that the first Michael was of a family that had been settled in Thames-side Surrey or Middlesex for several generations. Whether or not such a family came there directly from Yorkshire, or via Norfolk or Cambridgeshire, or via and other protracted migration, is a matter of speculation which may never be resolved.

No other family is known to have had as long an unbroken association with the Company of Watermen as the Laytons. There has always been a Layton waterman since the Great Fire; a fact commemorated by the Beadle Staff presented to the Company in 1965 by the late Dudley Edward Layton, whose son, James Layton, is the current Layton waterman. Some seem to have had other occupations concurrently with that of watermen, or perhaps after they had ceased to be active watermen. The first Michael was also a merchant; his grandson Thomas, who was waterman (along with his brother, Nathaniel) to Caroline of Ansrach, is referred to in the Indenture dated 1745, as a "gardner". (the produce gardens in and near Kew helped provision London - we would today probably call Thomas a 'market gardener'). John William Layton was a waterman (lighterman) and coal merchant. Perhaps there were mainly merchants who found it profitable to own their own water transport subsidiary, and for this purpose had to become licensed watermen. Recent Laytons, though retaining the association with the Worshipful Company, have not been involved in Thames traffic: William Layton (1845-1918) was a press correspondent; his son, Edward Scott Stacy Layton (1880-1954) was a businessman in the City; the late Dudley Edward Layton was an insurance underwriter at Lloyds, as was his son, James Michael Layton.
There is an early, if tenuous link with Australia in the family. In 1798, the great naturalist, Sir Joseph Banks, despatched to Australia a consignment of plants. He put them in the care of a horticulturalist, Mr George Suttar, who was emigrating with his bride to the colony. Suttar recorded his diary that the plants were transported on the first stage of their journey, from Kew to Greenhithe "by a decked sailing ship in charge of Mr Layton, the King's waterman". In 1798 there were two Layton watermen, the brothers John and Thomas, but neither were "King's watermen. Their father certainly had been; and their grandfather and great uncle had both been royal watermen; Mr Suttar was evidently mistaken about the precise royal appointments.