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Mammal

life science Maturity 5-7 Vital Level 3

Mammals are animals with hair.

Nine-banded-Armadillo white background.jpg
Nine-banded-Armadillo white background.jpg
They feed their babies milk. Most mammals give birth to live babies. Some small mammals are very smart. We are mammals too! Can you find hair on your arm?

39 words

Mammals are special animals. Most have hair or fur on their skin.

Nine-banded-Armadillo white background.jpg
Nine-banded-Armadillo white background.jpg
Mothers make milk to feed their babies. This helps the young grow strong.

Most mammals give birth to live babies. A few, like the platypus, lay eggs. Mammals come in many sizes. The blue whale is very large. The bumblebee bat is very small.

Many mammals are very smart. They can use tools to help them. Some can even sing or talk. It is fun to learn about them!

88 words

Mammals are a group of animals with special traits. Most mammals have hair or fur on their bodies.

Nine-banded-Armadillo white background.jpg
Nine-banded-Armadillo white background.jpg
They also have mammary glands. These are parts that make milk for babies. Most mammals give birth to live young. However, five species called monotremes lay eggs.

There are many kinds of mammals. They come in very different sizes. The blue whale is a giant animal. On the other side, the bumblebee bat is tiny.

Vampire bat white background.jpg
Vampire bat white background.jpg
Some mammals live in trees. Others swim in the sea or live underground.

Many mammals are very smart. They can use tools to solve problems. They also use sounds to talk to each other. Some use singing or even special sounds to find their way.

Mole white background.jpg
Mole white background.jpg
People have lived with mammals for a long time. We use them for food, work, and even as pets. Today, we must protect their homes so they stay safe.

161 words

{ "text": "Mammals are a special group of animals called vertebrates. They have many unique traits that set them apart from birds and reptiles.

Nine-banded-Armadillo white background.jpg
Nine-banded-Armadillo white background.jpg
Most mammals have hair or fur on their bodies. They also have mammary glands, which are parts that make milk to feed their young. Another key feature is a large brain area called the neocortex. They also have three tiny bones inside their middle ears. These traits help us understand how they live and grow.
Morganucodon.jpg
Morganucodon.jpg
\n\nMost mammals follow a similar way of growing and living. Most give birth to live young to protect them. This is called being viviparous. The most common group is the placental mammals. They use a temporary organ called a placenta to give nutrition to a baby during gestation.
Manatee white background.jpg
Manatee white background.jpg
However, five special species called monotremes are different because they lay eggs. This shows how much variety exists within a single group of animals.\n\nThe history of mammals is very long and amazing. Their ancestors split from the reptile lineage over 300 million years ago.
Docofossor NT flipped.jpg
Docofossor NT flipped.jpg
Early relatives were called synapsids, which lived during the Carboniferous period. Later, a group called therapsids became very successful on land. Mammals themselves grew from a group called cynodonts.
Morganucodon.jpg
Morganucodon.jpg
They became the main animals on land about 66 million years ago. This happened after the non-avian dinosaurs went extinct.\n\nThere are about 6,495 different species of mammals known today.
OrthoMaM v10b 2019 116genera circular tree.svg
OrthoMaM v10b 2019 116genera circular tree.svg
They are divided into 27 different orders. The largest groups include rodents, bats, and eulipotyphlans like moles.
Mole white background.jpg
Mole white background.jpg
Primates, such as humans and monkeys, are also a major group. Mammals come in all sizes. The blue whale is a huge animal that lives in the sea.
Manatee white background.jpg
Manatee white background.jpg
The tiny bumblebee bat is one of the smallest.
Vampire bat white background.jpg
Vampire bat white background.jpg
\n\nMammals are connected to our daily lives in many ways. Humans are actually part of the primate group of mammals. Long ago, during the Neolithic Revolution, humans began living with animals. This changed how people lived by moving from hunting to farming. ') , "media": [ "File:Nine-banded-Armadillo white background.jpg", "File:Cebus olivaceus", "File:Morganucodon.jpg", "File:Manatee white background.jpg", "File:Ornithorhynchus anatinus.jpg", "File:Docofossor NT flipped.jpg", "File:OrthoMaM v10b 2019 116genera circular tree.svg", "File:Mole white background.jpg", "File:Vampire bat white background.jpg", "File:Indian elephant" ] }

394 words

Mammals are a diverse class of vertebrate animals known scientifically as Mammalia. They are defined by several distinct biological characteristics that separate them from other groups like birds and reptiles. One primary feature is the presence of mammary glands. These glands produce milk to nourish their young. Most mammals also possess hair or fur on their bodies. Another key trait is a broad neocortex, which is a large region of the brain. They also uniquely have three bones located in the middle ear.

Morganucodon.jpg
Morganucodon.jpg

How mammals reproduce and develop varies across different groups. Most modern mammals are viviparous, meaning they give birth to live young. The largest and most species-rich group is the placental mammals. These animals use a temporary organ called a placenta. This organ allows the offspring to draw essential nutrition from the mother during gestation. However, there are exceptions to this rule. Five specific species known as monotremes actually lay eggs.

The classification of mammals is complex and has undergone many revisions. Scientists use different systems to group these animals. Carl Linnaeus first defined the class in 1758 using the Latin term "mamma." Today, researchers use molecular studies and DNA analysis to find new relationships. These studies suggest three major lineages of placental mammals: Afrotheria, Xenarthra, and Boreoeutheria. These groups diverged during the Cretaceous period, roughly 105 to 120 million years ago.

OrthoMaM v10b 2019 116genera circular tree.svg
OrthoMaM v10b 2019 116genera circular tree.svg

The evolutionary history of mammals spans hundreds of millions of years. Mammals belong to a larger group called Synapsida. This group split from the reptile lineage during the Carboniferous period, over 300 million years ago. Early synapsids, often called pelycosaurs, were not actually reptiles. Later, a more advanced group called therapsids became the dominant land vertebrates. Mammals eventually originated from cynodonts, which were an advanced group of therapsids. This transition occurred between the Late Triassic and Early Jurassic periods.

Docofossor NT flipped.jpg
Docofossor NT flipped.jpg

Mammals achieved great biological diversity during the Cenozoic era. After non-avian dinosaurs went extinct, mammals became the dominant terrestrial animals. This shift occurred about 66 million years ago. Today, there are approximately 6,495 recognized species of mammals. These species are organized into 27 different orders. The largest orders include rodents, bats, and eulipotyphlans, which contain animals like shrews and moles.

Mole white background.jpg
Mole white background.jpg
Other major orders include primates, even-toed ungulates, and Carnivora.

The physical variety among mammals is truly staggering in scale. They range from the tiny bumblebee bat to the massive blue whale. The blue whale may be the largest animal to ever live. Lifespans also vary greatly depending on the species. A shrew may live for only two years. In contrast, a bowhead whale can live for 211 years. While most mammals are quadrupedal, limbs have adapted for many environments. Some mammals fly in the air, while others live in the sea or underground.

Manatee white background.jpg
Manatee white background.jpg

Humanity has a deep and complex connection to the mammal group. During the Neolithic Revolution, humans began the domestication of many mammals. This transition allowed farming to replace hunting and gathering. As a result, human societies changed from nomadic groups to sedentary civilizations. Domesticated mammals have provided food, power for transport, and materials like leather. Today, mammals remain important in science as model organisms. However, many species face threats from human poaching and habitat destruction, such as deforestation.

558 words
🖼️ Images & Media (61)
File:OrthoMaM v10b 2019 116genera circular tree.svg
OrthoMaM v10b 2019 116genera circular tree.svg
File:Genera mammalium Ornithorhynchus anatinus.jpg
Genera mammalium Ornithorhynchus anatinus.jpg
File:Phylogenetic tree of marsupials derived from retroposon data (Paucituberculata).png
Phylogenetic tree of marsupials derived...
File:A hand-book to the marsupialia and monotremata (Plate XXXII) (white background).jpg
A hand-book to the marsupialia and...
File:Phylogenetic tree of marsupials derived from retroposon data (Notoryctemorphia).png
Phylogenetic tree of marsupials derived...
File:Phylogenetic tree of marsupials derived from retroposon data (Paramelemorphia).png
Phylogenetic tree of marsupials derived...
File:Phylogenetic tree of marsupials derived from retroposon data (Dasyuromorphia).png
Phylogenetic tree of marsupials derived...
File:A monograph of the Macropodidæ, or family of kangaroos (9398404841) white background.jpg
A monograph of the Macropodidæ, or family...
File:Nine-banded-Armadillo white background.jpg
Nine-banded-Armadillo white background.jpg
File:Natural history of the animal kingdom for the use of young people (Plate XV) (Myrmecophaga tridactyla).jpg
Natural history of the animal kingdom for...
File:DendrohyraxEminiSmit white background.jpg
DendrohyraxEminiSmit white background.jpg
File:Manatee white background.jpg
Manatee white background.jpg

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