Mastiff
Placed on this panel from 6 sequenced dogs, among 258 breeds.
Measured nearest to Bullmastiff, and nothing among the other 257 breeds is nearer. The smallest branch holding them both covers 0.7% of this tree.
The 12 breeds nearest to Mastiff.
The line starts at the tightest pairing this panel holds and ends at the widest separation measured on it, so how far along these marks sit is the answer to how close Mastiff really is to anything.
1
Bullmastiff2
Boerboel3Continental Bulldog4
Olde English Bulldogge5
Dogue de Bordeaux6
Boxer7
Tosa Inu8
Dogo Canario9
American Bulldog10
Cane Corso11
Majorca Mastiff12
French Bulldog
Bullmastiff2Boerboel3Continental Bulldog4Olde English Bulldogge5Dogue de Bordeaux6Boxer7Tosa Inu8Dogo Canario9American Bulldog10Cane Corso11Majorca Mastiff12French BulldogCloseness is measured from the genomes, and nothing else. It has no units and no dates. Two breeds sitting close together means their lines separate late in this data. It does not mean either one came from the other.