Some scientists estimate that ‘life’ began on our planet as early as four billion years ago. And the first living things were simple, single-celled, micro-organisms called prokaryotes (they lacked a cell membrane and a cell nucleus).

Prokaryotes were the earliest life forms, simple creatures that fed on carbon compounds that were accumulating in Earth’s early oceans. Slowly, other organisms evolved that used the Sun’s energy, along with compounds such as sulfides, to generate their own energy.

• Characteristics of earliest life forms.
• small (1-2 nanometers)
• single-celled.
• no external appendages.
• little internal structure.
• no nucleus.
• resembled today�s bacteria.
• in group called prokaryotes (“before nucleus”)

comb jelly

With their penchant for hunting, habitat destruction and the release of invasive species, humans undid millions of years of evolution, and swiftly removed this bird from the face of the Earth. Since then, the dodo has nestled itself in our conscience as the first prominent example of human-driven extinction.

An international team of scientists has just identified what they believe is the world’s first known dog, which was a large and toothy canine that lived 31,700 years ago and subsisted on a diet of horse, musk ox and reindeer, according to a new study.

14 Purest Dog Breeds

• #1- Afghan Hound – Is One of the oldest dog breeds. He also is one of the oldest hound breed dog. The history is debatable, but most acknowledge that the Afghan Hound history began about 8000 years ago.
• #3- Alaskan Malamute.
• #4- Basenji.
• #5- Chow-Chow.
• #6- Lhasa Apso.
• #7- Pekingese.
• #8- Saluki.

18 Dog Breeds with the Strongest Bite

• How Is a Dog’s Bite Strength Calculated?
• Doberman – 228 psi.
• Boxer – 230 psi.
• Pitbull – 235 psi.
• German Shepherd – 238 psi.
• American Bulldog – 305 psi.
• Siberian Husky – 320 PSI.
• Rottweiler – 328 psi.

Small breed dogs are more susceptible to dental disease than larger dogs, due to the anatomy of their mouths, heads and faces, along with other genetic features. The importance of dental health in all dogs cannot be understated. Oral disease is the single most common medical problem diagnosed in canines.

Top 10 Dog Breeds with the Worst Teeth

• #1 Dachshund. Though pawrific for getting into badger holes, the narrow muzzles of Dachshunds are prone to overbites.
• #2 Yorkshire Terrier.
• #4 Maltese.
• #5 Collie.
• #6 Lhasa Apso.
• #7 English Bulldog.
• #8 Cavalier King Charles Spaniel.
• #9 Pug.

At around 12 weeks, the deciduous teeth begin to fall out, and the permanent teeth begin to erupt. Normally by 6 months of age, all permanent teeth have erupted, and all deciduous teeth have fallen out.

5 Easy Ways to Keep Your Dog’s Teeth Clean

1. Brush Your Dog’s Teeth with Delicious Toothpaste. For both dogs and humans, teeth brushing is the foundation of good oral health.
2. Nibble on Dog Dental Chews.
3. Spritz Dog Dental Spray.
4. Gnaw on Chew Toys.
5. Attend Regular Professional Veterinarian Cleanings.

Small breeds such as the Boston terrier, Pekingese, French bulldog, English bulldog, King Charles spaniel, pug, Lhasa apso and shih tzu are commonly observed developing underbites. These are the most common underbite dog breeds, but the condition is possible in most dogs.

This type of malocclusion is seen in dogs with underbites. Upper and lower jaw and teeth alignment can be a bit tricky in dogs. As long as a dog can comfortably chew and eat solid food and their bite is functional, an underbite malocclusion can be considered both normal and healthy.

Puppy Underbite Underbite in puppies may sometimes be corrected using braces. However, extraction and filling can also be applied. Treatment options for a puppy with underbites will vary depending on the type of malocclusion your pet faces, his age, health status, and other factors.

Severe injuries and tumors may result in underbites as well. In a perfect world, an underbite would resolve itself over time. Unfortunately, this is rarely the case and treatment is necessary to correct an underbite.

As a child ages, the underbite usually becomes worse with age, particularly during the growth spurt that occurs in the early teenage years (9-14). After this growth spurt, the growth of the jaw becomes stable and stops around mid-teenage years for females and late teenage years for males.

As a general rule, to correct underbite without surgery in adults, there are three main options: Invisalign, braces, and cosmetic procedures like veneers or crowns. Surgical underbite correction is generally only necessary when there is a more serious skeletal problem responsible for the bad bite.

Why? Early treatment (aka Phase 1 treatment) between the ages of 7 and 10 may be most effective at correcting this bite. Widening the upper jaw at a young age can allow for the permanent teeth to erupt in a better position than they otherwise would have.