According to the thermometer, it appears we have officially reached the dog days of summer, but where did the term "dog days of summer" come from?

It's actually in reference to the Dog Star, Sirius, the second brightest star in the sky. People once thought it actually added to the summer heat of the sun. The word Sirius means scorching or burning and was also the name of Icarius' dog, which was turned into a star after Icarius' fatal venture into the sun.

Ancient Greeks referred to summer days as dog days, believing that only dogs were crazy enough to go out in the heat.

Many animals have adapted some unique ways to deal with heat waves. Tortoises and other species find protection from the extremes of heat by hiding out in burrows during the mid-day. Some animals, like elephants and lions, find the hottest part of the day to be the best nap time, and some don't even bother getting up at all during daylight hours. Far better to look for dinner when it's cooler.

The fennec fox and the elephant have built-in air conditioners. Their over-sized ears keep blood vessels very close to the surface of the skin. They will move their ears about when it's particularly hot to circulate air around those blood vessels. This cools down the blood that returns to the heart and, thus, cools the rest of the body.

Most hoofed animals like antelope and cattle will seek out shade when it's hot. Zebras are no different; however, some new studies suggest that camouflage may not be the only reason why they have black and white stripes. It is possible that their color variation actually helps to regulate their body temperature. During the coolness of the night, the dark stripes have retained heat from the day, keeping the body warm. In the heat of the afternoon, the white stripes reflect the heat, cooling the body.

All cats have padded feet, but some have furry feet with haired soles to protect them from hot desert sand. And unlike many cat species, tigers and jaguars love spending time in the water. It's not uncommon for them to snooze away the hottest part of the day partially submerged in a pool of water. Even our animals here at the zoo often can be seen lounging in their own pools. Not only the tigers, but the elephants, bears and otters enjoy a refreshing dip in the water.

Anyone with a dog or a cat knows when it's getting warm with the excess of hair around the house. And if you've seen our bison or camels lately, you know they, too, are undergoing some dramatic shedding of their own!

And then there's migration. Some animals (and people) are just smart enough to leave when the weather gets too hot.

The zoo does a lot to keep our animals comfortable in the heat. Some animals are provided with pools, mud wallows and shade structures. Many get special icy treats or enjoy misters to cool off. The red pandas are provided with soda bottles filled with water and frozen, so they can snuggle up with them to cool off. Quite a few of the animals do have air conditioned quarters, and on the hottest days will be given access to go inside if they choose.

Our pets at home deserve as much care and protection during these hot, summer days as the animals here at the zoo. Here are just a few tips to help your pets enjoy the lazy days of summer.

Never leave your pets unattended in your car. Even when the temperature is only 78 degrees outside, the interior of your car will exceed 110 degrees in only 25 minutes, even with the windows partially opened.

Make sure your pet has fresh, clean, cool water available at all times.

If your pet is outside during the day, be sure there is a well-ventilated, shady place to rest. Even doghouses must be placed in the shade or the inside will become as hot as your vehicle.

Avoid taking your pet for a walk during the heat of the day. Save exercise time for early morning or late evening. Not only can your pet overheat, but hot asphalt and pavement can burn your pet's paws.

Have your pet groomed to remove that heavy coat.

Pets can sunburn, too! Lighter-colored animals are more prone to skin cancer, so be sure to limit sun exposure.

With a little precaution, a fine mud wallow and some frozen treats, the animals we love and appreciate at the zoo and at home can enjoy some fun in the sun!