New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Dog anatomy

The anatomy of dogs varies tremendously from breed to breed, more than in any other animal species, wild or domesticated. And yet there are basic physical characteristics that are identical among all dogs, from the tiny Chihuahua to the giant Irish Wolfhound. Like most predatory mammals, the dog has powerful muscles, a cardiovascular system that supports both sprinting and endurance, and teeth for catching, holding, and tearing. The dog's ancestral skeleton provided the ability to run and leap. Their legs are designed to propel them forward rapidly, leaping as necessary, to chase and overcome prey. Consequently, they have small, tight feet, walking on their toes; their rear legs are fairly rigid and sturdy; the front legs are loose and flexible, with only muscle attaching them to the torso. Although selective breeding has changed the appearance of many breeds, all dogs retain the basic ingredients from their distant ancestors. Dogs have disconnected shoulder bones (lacking the collar bone of the human skeleton) that allow a greater stride length for running and leaping. They walk on four toes, front and back. The dog's ancestor was about the size of a Dingo, and its skeleton took about 10 months to mature. Today's toy breeds have skeletons that mature in only a few months, while giant breeds such as the Mastiffs take 16 to 18 months for the skeleton to mature. Dwarfism has affected the proportions of some breeds' skeletons, as in the Basset Hound.

Related Stories
 


Plants & Animals News

October 8, 2025

Kobe University researchers found that orchids rely on wood-decaying fungi to germinate, feeding on the carbon from rotting logs. Their seedlings only grow near deadwood, forming precise fungal partnerships that mirror those seen in adult orchids ...
Researchers at KAUST have confirmed that the Red Sea once vanished entirely, turning into a barren salt desert before being suddenly flooded by waters from the Indian Ocean. The flood carved deep channels and restored marine life in less than ...
Scientists studying tiny roundworms have uncovered how the secrets of a long life can be passed from parents to their offspring — without changing DNA. The discovery shows that when certain cellular structures called lysosomes change in ways that ...
New research reveals that deep-sea mining could dramatically threaten 30 species of sharks, rays, and ghost sharks whose habitats overlap with proposed mining zones. Many of these species, already at risk of extinction, could face increased dangers ...
HydroSpread, a breakthrough fabrication method, lets scientists build ultrathin soft robots directly on water. These tiny, insect-inspired machines could transform robotics, healthcare, and environmental ...
Billions of years ago, Earth’s atmosphere was hostile, with barely any oxygen and toxic conditions for life. Researchers from the Earth-Life Science Institute studied Japan’s iron-rich hot springs, which mimic the ancient oceans, to uncover how ...
Fungi may have shaped Earth’s landscapes long before plants appeared. By combining rare gene transfers with fossil evidence, researchers have traced fungal origins back nearly a billion years earlier than expected. These ancient fungi may have ...
A team of researchers tested morin, a plant compound, against gum disease bacteria and found strong antimicrobial benefits. By encapsulating it in polymers, they created a powdered form for oral hygiene products. This could replace antibiotics, ...
Scientists have uncovered a dangerous hidden feature in Black Mamba venom that explains why antivenoms sometimes fail. The study revealed that several mamba species launch a dual neurological attack, first causing limp paralysis and then unleashing ...
Scientists have kept a tiny slice of cochlea alive outside the body, directly witnessing how hair cells amplify sound. The finding confirms a universal principle of hearing and could pave the way for long-sought treatments for hearing ...
Researchers have revealed how polymyxins, crucial last-resort antibiotics, break down bacterial armor by forcing cells to overproduce and shed it. Astonishingly, the drugs only kill bacteria when they’re active, leaving dormant cells untouched. ...
Human fertility hinges on a delicate molecular ballet that begins even before birth. UC Davis researchers have uncovered how special protein networks safeguard chromosomes as eggs and sperm form, ...

Latest Headlines

updated 12:56 pm ET