What is the Difference Between Rodents and Lagomorphs

The main difference between rodents and lagomorphs is that rodents have two incisors in the upper jaw, whereas lagomorphs have four. 

Rodents and lagomorphs are two mammals that are vertebrate animals characterized by the presence of milk-producing mammary glands.   

Key Areas Covered

1. What are Rodents
– Definition, Characteristics, Importance
2. What are Lagomorphs
– Definition, Characteristics, Importance
3. Similarities Between Lophotrochozoa and Ecdysozoa
– Outline of Common Features
4. Difference Between Lophotrochozoa and Ecdysozoa
– Comparison of Key Differences

Key Terms 

Lagomorphs, Rodents

What are Rodents

Rodents are mammals characterized by continuously growing incisors in the upper and lower jaws. They represent about 40% of the mammal species. They live in almost all terrestrial habitats. Rodents include mice, squirrels, gerbils, dormice, gophers, pocket mice, rats, beavers, kangaroo rats, porcupines, springhares, and many others. Also, the teeth of rodents are specialized for chewing and gnawing. A pair of incisors occur in the upper jaw. Additionally, incisors lack enamel on the back of the tooth. A large gap occurs between incisors and molars. Rodents have multiple pairs of premolars and molars. Rodents do not have canine teeth. Further, they have a complex jaw musculature. They have a penis bone.

Figure 1: Rodents

Furthermore, rodents eat various foods, including fruit, leaves, seeds, and small invertebrates. The caecum is the structure by which rodents digest cellulose. It contains digestive enzymes which break down plant material into digestible components. Also, rodents play a key role in communities by serving as prey for mammals and birds.  

What are Lagomorphs

Lagomorphs are another group of mammals that have hair and four limbs. They have mammary glands that produce milk. Also, they are endotherms. Lagomorphs include rabbits, pikas, and hares. Hares and rabbits have long ears, short tails, and strong hind limbs. Also, pikas have short and rounded ears, no external tail, and less well-developed hind limbs. On the other hand, lagomorphs are small to medium-sized terrestrial herbivores. They do not have paw pads. Instead, they have paws entirely covered with hair. Unusually to the other mammals, lagomorphs have larger females than males.

Figure 2: Lagomorph

Moreover, pikas are small mammals native to western North America and Central Asia mountains. They are about 15 cm long, with grayish brown, small rounded ears, silky fur, and no tail. Their four legs are nearly equal in length. Some species of lagomorphs live in scree, while others construct burrows. The lifespan of the rock-dwelling species is higher than others. Also, hares are medium-sized mammals native to Europe, Asia, Africa, and North America. The size of the hares varies from 40 to 70 cm in length. Significantly, they have long, powerful back legs. They are grayish-brown in color. In comparison, rabbits are much smaller than hares. Their size varies from 20 to 50 cm.    

Similarities Between Rodents and Lagomorphs

• Rodents and lagomorphs are two mammals that have characteristic milk-producing glands.
• Also, they contain neocortex regions in the brain, hair or fur, and three middle ear bones.
• Their incisor teeth grow continuously throughout their lives.
• They have smooth-surfaced cerebrum. 

Difference Between Rodents and Lagomorphs

Definition

Rodents refer to any order (Rodentia) of relatively small gnawing mammals (such as a mouse, squirrel, or beaver) that have a single pair of incisors with a chisel-shaped edge in both jaws. In contrast, lagomorphs refer to any order (Lagomorpha) of gnawing herbivorous mammals having two pairs of incisors in the upper jaw, one behind the other, comprising rabbits, hares, and pikas.

Incisors 

Rodents have two incisors in the upper jaw, while lagomorphs have four incisors. 

Diet

Rodents eat both meat and vegetables, while lagomorphs are herbivores. 

Conclusion

In brief, rodents and lagomorphs are two mammals that contain milk-producing glands. Rodents have two incisors in the upper jaw. They eat both meat and vegetables. In comparison, lagomorphs have four incisors, and they are herbivores. Therefore, the main difference between rodents and lagomorphs is the number of incisors in the upper jaw.   

References:

1. Klappenbach, L. (2019, April 5). Why rodents play a key role in our Society. ThoughtCo. 
2. Encyclopædia Britannica, inc. (n.d.-f). Lagomorph. Encyclopædia Britannica. 

Image Courtesy:

1. “The Pika” By Karunakar Rayker – Own work (CC-BY 2.0) via Commons Wikimedia
2. “Goldmantelziesel” By Eborutta at German Wikipedia – Own Work (CC-BY SA 3.0) via Commons Wikimedia