What Are Trilobites?

What are trilobites?

Trilobites are an extinct group of arthropods (jointed-legged animals) known from more than 10,000 fossil species.

The group Trilobita existed from early in the Cambrian Period (520 million years ago) until the end of the Permian Period (250 million years ago).The name Trilobita is derived from the three (tri-) lobed structure of the exoskeleton, which has a raised central lobe (or axis) and a pair of side lobes, called Pleurae.

Ferns first appear in the fossil record in the early-Carboniferous period.
By the Triassic, the first evidence of ferns related to several modern families appeared.

Year 10 EvolutionName: ______

Answer the questions based on the Geological Time Scale

1. What does the geologic time scale represent?
   ______
2. Scientists have devised the Geologic Time Chart so that Time can be understood from the largest and most general intervals, or units, to the smallest, most specific intervals.

Arrange these geological time intervals from largest to smallest:
periods eons epochs eras

1. How old is our Earth? ______
   
2. What is the difference between eukaryotic and prokaryotic cells? Give examples.
   ______
   ______
3. Fill in the table with information about Era’s (using the information below)
   1. Precambrian Era (earliest forms of life, such as bacteria and blue-green algae; later in the period, invertebrates such as jellyfish).
   2. Paleozoic Era (Pangaea; invertebrate life, such as trilobites, later in the era, followed by development of vertebrates, including fish; development of vertebrates, amphibians, and the beginnings of reptiles; development of simple plants, such as mosses and ferns)
   3. Mesozoic Era (Pangaea separates into continents; "Age of Reptiles"; dinosaurs, flowering plants, small mammals and birds)
   4. Cenozoic (Present Era) Ice Age; mammoths; gradual development of mammals, birds and other animals recognizable today; humans; flowering plants, forests, grasslands.)
   More:
   

1. Which periods did Dinosaurs live on Earth?
   ______
2. Arrange the animals in terms of evolution from the oldest to the youngest.
   reptiles, invertebrates, bacteria, fish, mammals, amphibians, birds
   ______
   
3. Give 2 differences between amphibians and reptiles in terms of their evolution and living habitats.
   ______
   ______
   
4. Which type of plant was the first land plant? Conifers, Angiosperms, Mosses and Ferns
   ______
   
5. Arrange these 4 types of plants in order of primitive to most recently evolved.
   Conifers, Angiosperms, Mosses and Ferns
   ______
   
6. How could plants like Conifers, Ferns and Conifers grow bigger in size compared to mosses?
   ______
   
7. Explain why insects have evolved most successfully to colonise the Earth?
   ______
   ______
   
   

1. In Ordovician Period, trilobites became dominant. What type of animal did trilobites belong to? How long did they live on Earth?
   ______
   ______
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1. When did first human evolve on Earth?
   ______
   

1. When did mammal start to evolve?
   ______