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

August 24, 2025

Ripple bugs’ fan-like legs inspired engineers to build the Rhagobot, a tiny robot with self-morphing fans. By mimicking these insects’ passive, ultra-fast movements, the robot gains speed, control, and endurance without extra ...
Researchers discovered that bees use flight movements to sharpen brain signals, enabling them to recognize patterns with remarkable accuracy. A digital model of their brain shows that this movement-based perception could revolutionize AI and ...
A new study reveals that the majority of Earth’s species stem from a few evolutionary explosions, where new traits or habitats sparked rapid diversification. From flowers to birds, these bursts explain most of the planet’s ...
Scientists have uncovered a startling split in the venom of Australia’s Eastern Brown Snake. In the south, bites cause rock-solid blood clots, while in the north, they trigger flimsy clots that ...
Planting more trees can help cool the planet and reduce fire risk—but where they are planted matters. According to UC Riverside researchers, tropical regions provide the most powerful climate benefits because trees there grow year-round, absorb ...
Kelp forests bounce back faster from marine heatwaves when shielded inside Marine Protected Areas. UCLA researchers found that fishing restrictions and predator protection strengthen ecosystem resilience, though results vary by ...
MSU researchers discovered that microbes begin shaping the brain while still in the womb, influencing neurons in a region critical for stress and social behavior. Their findings suggest modern birth practices that alter the microbiome may have ...
NASA-backed simulations reveal that meltwater from Greenland’s Jakobshavn Glacier lifts deep-ocean nutrients to the surface, sparking large summer blooms of phytoplankton that feed the Arctic food ...
Roughly two-thirds of all atmospheric methane, a potent greenhouse gas, comes from methanogens. Tracking down which methanogens in which environment produce methane with a specific isotope signature is difficult, however. UC Berkeley researchers ...
Scientists have engineered a groundbreaking cancer treatment that uses bacteria to smuggle viruses directly into tumors, bypassing the immune system and delivering a powerful one-two punch against cancer cells. The bacteria act like Trojan horses, ...
Weaver ants have cracked a teamwork puzzle that humans have struggled with for over a century — instead of slacking off as their group grows, they work harder. These tiny architects not only build elaborate leaf nests but also double their pulling ...
Over 15 years of fossil excavations in Tanzania and Zambia have revealed a vivid portrait of life before Earth s most devastating mass extinction 252 million years ago. Led by the University of ...

Latest Headlines

updated 12:56 pm ET