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What is the difference between mammals and reptiles?
What are the three types of mammals?
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Why do reptiles have a smaller skull than mammals?
Feb 27, 2018 · The main difference between mammals and reptiles is that mammals have mammary glands to feed their babies with milk whereas reptiles do not have mammary glands. Turtles, tortoises, lizards, snakes, crocodiles, alligators, and tuatara are reptiles while marsupials, monotremes, and placentals are the three types of mammals. Key Areas Covered. 1.
Apr 24, 2018 · The majority of reptiles lay eggs; most mammals give birth to live young. There are exceptions, however. Some snakes, including boas, produce live offspring. Two primitive kinds of mammals--the echidna and the duck-billed platypus, known collectively as monotremes--lay leathery eggs similar to those of reptiles.
- Bob Strauss
- Invertebrates. The first animals to evolve, as far back as a billion years ago, invertebrates are characterized by their lack of backbones and internal skeletons as well as their relatively simple anatomy and behavior, at least compared with those of most vertebrates.
- Fish. The first true vertebrates on Earth, fish evolved from invertebrate ancestors about 500 million years ago and have dominated the world's oceans, lakes, and rivers ever since.
- Amphibians. When the first amphibians evolved from their tetrapod ancestors 400 million years ago, they quickly became the dominant vertebrates on Earth.
- Reptiles. Reptiles, like amphibians, make up a fairly small proportion of terrestrial animals, but as dinosaurs they ruled the Earth for over 150 million years.
Higher mammals—apart from the egg-laying mammals—do not have yolk in their eggs but, having passed through an evolutionary stage of animals with yolky eggs, retain, particularly in gastrulation, features common to reptiles (and birds, which also had reptilian ancestors).
- Boris Ivan Balinsky
Main Differences between Reptiles and Mammals. Reptiles have scales on their bodies while mammals have hair on their bodies. Reptiles lay eggs while mammals give birth to live young ones. Reptiles have a low metabolic rate while mammals have a high metabolic rate. Reptiles have three-chambered hearts while mammals have four-chambered hearts.
Sep 23, 2021 · The amniotes—reptiles, birds, and mammals—are distinguished from amphibians by their terrestrially adapted (shelled) egg and an embryo protected by amniotic membranes. The evolution of amniotic membranes meant that the embryos of amniotes could develop within an aquatic environment inside the egg.
Jan 9, 2018 · In Reptiles, the skin is covered by scales while in mammals it is covered with hair or fur and sebaceous glands. Anatomy: 1. Osteology: Skull in reptiles is smaller, in proportion to their body, when compared to that of mammals.
