Principle of faunal succession
The principle of faunal succession is like a big story about how animals change over time, and it helps scientists figure out how old certain rocks are.
So, imagine you go on a hike and find some rocks. You might notice that some rocks have fossils in them – old animals that left their remains behind. Scientists use these fossils to figure out how old the rocks are by looking at the order they appear in.
This is because animals and plants evolve over time, and different species are around at different times. For example, maybe 100 million years ago there were huge, scary dinosaurs walking around, but today there aren't any. So if you find a fossil of a dinosaur, you know that the rock it's in is at least 100 million years old.
But how do scientists know which animals were around when? They use the principle of faunal succession! This principle says that different groups of animals lived during different time periods, and so if you find certain fossils together in a rock, you can tell how old it is.
For example, let's say you find a rock with a fossil of a trilobite and a fossil of a fish. Scientists know that trilobites lived a long time ago, and fish came later. So they can tell that the rock is older than the rocks with only fish fossils.
Overall, the principle of faunal succession helps scientists put together a timeline of the Earth's history, and understand how different animals and plants evolved over time.
So, imagine you go on a hike and find some rocks. You might notice that some rocks have fossils in them – old animals that left their remains behind. Scientists use these fossils to figure out how old the rocks are by looking at the order they appear in.
This is because animals and plants evolve over time, and different species are around at different times. For example, maybe 100 million years ago there were huge, scary dinosaurs walking around, but today there aren't any. So if you find a fossil of a dinosaur, you know that the rock it's in is at least 100 million years old.
But how do scientists know which animals were around when? They use the principle of faunal succession! This principle says that different groups of animals lived during different time periods, and so if you find certain fossils together in a rock, you can tell how old it is.
For example, let's say you find a rock with a fossil of a trilobite and a fossil of a fish. Scientists know that trilobites lived a long time ago, and fish came later. So they can tell that the rock is older than the rocks with only fish fossils.
Overall, the principle of faunal succession helps scientists put together a timeline of the Earth's history, and understand how different animals and plants evolved over time.
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