Dogs have short crowns. The crowns of the first and second maxillary incisors are three-pointed, with canine teeth in the middle and small peaks on both sides. The other front teeth have two small peaks, and the canine teeth are conical and extremely sharp, which is a powerful weapon for attack and self-defense. The front teeth are three-pointed, and the Japanese teeth are multi-pointed.
As long as the dog feels a little hot, it will open its mouth and stick out its tongue to gasp, and it can secrete a lot of saliva instead of sweat. Dogs evaporate saliva to give off heat and lower their body temperature.
They drool a lot and absorb heat through saliva evaporation to lower their body temperature. When the weather is hot, it is impossible to cool down smoothly by this method alone. Therefore, it is difficult for dogs to lower their body temperature, because their respiratory organs are short, they are not good at regulating their body temperature, and they are particularly afraid of heat, so they should pay more attention.
Extended data:
Canine ancestors
Dogs are domesticated by wolves. As early as the era of hunting and gathering, people have domesticated dogs as hunting assistants. So dogs are the earliest domesticated domestic animals. Dog bones have been unearthed in Cishan, Wu 'an, Hebei, Peiligang, Xinzheng, Henan, Hemudu, Yuyao, Zhejiang, which proves that it has a long history of domestication.
No one knows exactly when the first interaction between man and wolf took place. Some scientists think it may be 50,000 years ago, because it took wild wolves at least so long to show today's genetic differences.
At that time, humans and wolves were distributed in many places on the earth's surface, and the evolution process may have occurred in several different areas. Some scholars believe that wolves were domesticated by wild wolves as domestic animals, that is, dogs, before 14000 years, and were used for playing, hunting and housekeeping.
References:
Baidu encyclopedia-dog