Question

Wart hogs with small snouts, when crossed together, produce approximately twice as many smallsnouted progeny as largesnouted progeny. This is a consistent trend when sufficient progeny are produced. What type of inheritance does this suggest?

Answer 1

The consistent trend of warthogs with small snouts producing twice many small-snouted offspring compared to large-snouted ones suggests inheritance through incomplete dominance, with an intermediate phenotype resulting from heterozygous pairings.

Step-by-step explanation:

Inheritance Patterns in Warthogs

When warthogs with small snouts, when crossed, consistently produce roughly twice as many small-snouted progeny as large-snouted ones, this suggests a pattern of inheritance known as incomplete dominance.

In incomplete dominance, the resulting phenotype of the heterozygote is intermediate between the phenotypes of the homozygotes. Similar to the snapdragon Antirrhinum majus, where a cross between parents with homozygous white (CWCW) and red (CRCR) flowers produces offspring with pink flowers (CRCW), the warthog snout size can show a phenotypic ratio of 1:2:1 in the offspring being small-snouted, intermediate, and large-snouted respectively.

If we denote the allele for large snouts as 'L' and small snouts as 'S', the genotypic ratio of the self-cross of heterozygotes (LS) would be 1 LL:2 LS:1 SS, implying incomplete dominance of the L allele over the S allele for snout size.