Rex

The animal's rarest line = the share of living animals that carry the same founder line. The lower the number, the rarer the genes.

• 0 % means nobody else carries that line; 40 % means almost half of the living population does.
• Computed from the pedigree up to 30 generations; unknown parents hide lines, so the number can be higher than reality.
• To keep the gene pool diverse, pair animals from rare lines with common ones, not two rare animals together.

Average lifespan of deceased ancestors (parents, grandparents, great-grandparents) compared with the population median.

• Only ancestors with a precise death date count; living ancestors are not included, so young animals often have no value.
• Above the population median suggests a long-lived line, below it a shorter life — but it is a small sample.
• Lifespan is driven by care and by the age at which the animal entered the registry; it is not only genetics.