Dogs with hard-working genes - Kesler Science Weekly Phenomenon and Graph

My family has a great dog - she's soft, friendly, easy going, and follows commands pretty well. What I find funny is the name of her type: she's a "sheepadoodle," a mix between an English sheepdog and a poodle. I know people with labradoodles (labrador + poodle) and goldendoodles (golden retriever + poodle) too. All these doodle names crack me up. 😆

Why are all these dogs being mixed with poodles? Allergies! Poodles have genetic traits that make them great for people who are usually allergic to dogs. Breeders noticed and created hybrids with fluffy family dogs that people with allergies can't usually own.

This got me thinking about other dog traits and the jobs dogs have been bred for throughout history. There were some weird and wonderful genetic traits among hard-working dogs in the past!

Here's a weird example from history: when roasting meat over a fire was popular in the 1600's, innkeepers created a little dog called the "turnspit dog", or Canis vertigus, to help in the kitchen. They were bred to be short with great stamina, and they would walk on a large wooden wheel to turn a spit over a fire. It wasn't a great job, so thankfully, once mechanical spit-turners were invented, people switched away from using dogs in kitchens. (The breed slowly faded in popularity, so there are no Canis vertigus around today.)

The Norwegian Lundehund is another dog breed that also dates back to the 1600's. The Lundehund's super power is that it has extra toes! This makes it an expert climber of rocky terrain when searching for birds or eggs.

The Newfoundland dog has a water-resistant double coat, webbed feet, and the endurance of a marathon runner. Newfoundlands were celebrated in the past as water rescue dogs with the ability to swim out to and save stranded sailors and fishermen. Today they're mostly pets known for their good nature - and their impressive drooling. 😆

You've probably heard that dalmatians make great firehouse dogs because they're deaf and can't hear the sirens. While it's true that about 30% of dalmatians are congenitally deaf, their link to the fire department goes back even deeper. Back in the time of horse-drawn transportation, dalmatians would run alongside carriages to keep the horses calm. When fire equipment was pulled by horses to hectic fire scenes, it just made sense to bring the calm carriage dogs to make the horses feel better along the way.

The genetic trait of size has a lot to do with the ways dogs can help people. For example, the dachshund was bred to be long and small so it could fit into badger dens. That made me wonder - do dogs of different sizes all grow in the same patterns? Check out this graph of dog growth rates:

Here are some questions I might ask my students if we analyzed this graph together in class:

💡By what age do medium sized dogs seem to stop growing? The growth curve for medium sized dogs flattens out at around 8 - 10 months. 

💡What is the weight difference between full grown giant breeds and full grown toy breeds? The graph shows that full grown giant dogs are nearly 150 pounds. Adult toy breeds are about 5 pounds. The weight difference would be about 145 pounds. 

💡What is different about the rate of growth for giant and large dogs versus the rate of growth for medium, small, and toy dogs? Medium, small, and toy dogs are pretty much finished growing after eight months, but large and giant dogs continue to grow for a year and half!

💡During what months does each dog size reach half their full-grown weight? Is there anything surprising about this? All the dogs reach half their full-grown size no later than six months, even if they will continue growing for more than a year longer!