What are link animals

BioTOP 3, textbook

Make a model of a stone core with 1 Make. You need snail shells and plaster of paris, which you mix with water. Pour the plaster of paris into the shell and rock it gently so that the mixture can fill the shell well. Now let the plaster filling dry undisturbed. After a few days you can remove the surrounding snail shell. You have now received the model of a stone core. Now compare the work steps on your model with the phases of stone core formation in the formation of fossils. B 4 Similarity of the embryos in reptiles, birds and mammals (humans) B 5 The platypus 41 Geological history Summary Fossils can be divided into fossils, stone cores, imprints and body fossils. Bridging animals are transitional forms that confirm the gradual development of living things. Living fossils are living things that have remained unchanged over millions of years. Evolution is understood to mean the gradual development of living beings. Bridging animals Bridging animals are transitional forms that confirm the gradual development of living things. The most famous bridge animal is the Archeopteryx, the link between reptiles and birds (see page 54). The Australian platypus is a bridging animal that is still alive today ( B 5). It lives in water and combines the characteristics of mammals and reptiles. Like reptiles, it lays eggs, but the young are suckled like mammals. The milk seeps into the animal's fur through glands on the belly and is licked off by the young animals. Similar to reptiles, the beaked animals have a cloaca that serves as an excretion and sexual opening. Male platypus also have a poison gland that ends in the heel spurs of their hind legs. This poison gland is reminiscent of the fangs of some snakes. The platypus is evenly warm, but its body temperature is subject to large fluctuations. Living fossils Living fossils are animals or plants that are very reminiscent of the original fossil forms. In the course of evolution, these living beings have not or hardly changed for millions of years. Living fossils give us insights into the lives of their relatives that we only know as fossil finds. They also show us that the living world of bygone times consisted primarily of different organisms than ours today. The relationship to long-extinct animals can be seen in living fossils. Living fossils include, for example, the coelacanth, which you will get to know on page 50. The ginko tree and the sequoia tree are also living fossils. For testing purposes only - property of the publisher n sich öbv

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