The Papillon (PAP ee yawn) is a lively breed of very small dogs that love to do tricks and follow their owners everywhere. The dogs pictured are both Papillons. A Papillon with drop ears is called a Phalene (fah LEHN). In French, Papillon means “butterfly,” and Phalene means “moth.”

Question

Paintings and historical records show that hundreds of years ago, all Papillons were Phalenes. If Papillons were only bred to other Papillons, how could the variety with stand-up ears first appear?
(5 Points)

The allele for stand-up ears could be recessive, so it wouldn’t show up until later.

Recent improvements in nutrition could cause the dogs’ ears to stand up with no genetic change.

Stand-up ears could provide more fitness for Papillons.

A random mutation during meiosis could have created the first puppies with stand-up ears.

Answer 1

The most plausible explanation for how the variety with stand-up ears (Papillons) first appeared is:

A random mutation during meiosis could have created the first puppies with stand-up ears.

This is because genetic mutations can occur naturally and may lead to new traits appearing in a population. If a random mutation caused a change in the genes responsible for ear structure, it could result in the first Papillon puppies having stand-up ears, even if they were bred from Phalenes at the time. The other options are less likely explanations for the emergence of this trait.