Classification and Evolution
Starter: How many different ways could I split these objects into 2 groups?
Classification All living things can also be grouped how do we decide which groups to put them into? We look at their features.
The 5 Kingdoms Living things can all be divided into one of 5 kingdoms. What kingdom do humans belong to?
Animals Each kingdom is further classified into smaller and smaller groups. The groups are based on the features of the animals and also how closely they are related to each other.
Animal groups
Your turn -What features do animals in the 5 vertebrate groups share? Group Mammals Birds Reptiles Features only found in this group. Fur/hair Produce milk Feathers Beaks Dry scales Fish Amphibians Wet scales Gills Moist skin Gills and lungs
What is a species? The smallest group an organism can be in is a species. Animals in the same species are similar to each other.
What is a species? Which of these images show members of the same species?
What is a species? Which of these images show members of the same species? 2 species of penguin 2 jaguars Members of the same species can appear to be very different to each other the real test is 2 dogs Asian and African Elephants whether or not they can breed together to produce fertile offspring.
Your turn answer in your book 1. What is a species? 2. Lions and tigers can breed together to make Ligers. Ligers are infertile. Why are lions and tigers not the same species?
Classification and Evolution Because organisms can seem to be alike due to their features we can assume that they are closely related when they are not. Scientists can now use evolutionary information to see the relationships between organisms based on their common ancestors.
Some relationships which may surprise you Some animals have been found to be much more closely related to other species than they appear by looking at their evolutionary history and genetic testing.
Some relationships which may surprise you The closest living relative to the two elephant species the rock hyrax!
Some relationships which may surprise you Dolphins and whales are closely related to hippos!
Some relationships which may surprise you Rhinos are closely related to horses!
Some relationships which may surprise you Hyenas are closely related to civets!
We can show evolutionary relationships in evolutionary trees.
We can show evolutionary relationships in evolutionary trees.
We can show evolutionary relationships in evolutionary trees.
We can show evolutionary relationships in evolutionary trees.
Evolutionary trees The further something is up the evolutionary tree the more recently it branched from the other species on the tree. Species which are more closely related are closer on the tree.
Look at this evolutionary tree showing some mammal species. 1. Which is the most closely related animal to the human? Green monkey 2. Which animal is a close relative of both camel and deer? Pig
Giant Pandas and Red Pandas People thought that giant pandas and red pandas were closely related because they are the only animals which have a wrist thumb and they both eat bamboo. They have an ecological relationship. But they are more like other animals like racoons (red panda) and bears (giant pandas) in their other features so the evolutionary relationship didn t match up. Scientists recently found fossils of an ancestor of the red panda which also has the wrist thumb which shows that the feature evolved separately. Now the evolutionary and ecological relationships match up.
Giant Pandas and Red Pandas Common Ancestor Evolution of the wrist thumb
Your turn Answer the questions on the sheet.
The diagram shows the evolution of a group called the primates. (a) Which primate evolved first? (1) (b) Name two primates that developed most recently from the same common ancestor as humans. (2) Lemur Gorilla and Chimpanzee
The diagram shows an evolutionary tree for a group of animals called primates. The names of extinct animals are printed in italics e.g. Nycticeboides. The drawings show animals that are alive today. (i) How many million years ago did Karanisia first appear? (1) 40 42million years (ii) During which geological period did the Apes and Monkeys begin to evolve? (1) Palaeocene (iii) Which group of primates alive today are the closest relatives of the Lorises? (1) Bush babies
The diagram shows an evolutionary tree for humans based on a study of fossils. (a) When did Australopithecus afarensisfirst appear? (1) 3.75 million years ago (b) Which species was the direct ancestor of Paranthropusboisei? (1) (Paranthropus) aethiopicus (c) Which species is most closely related to Homo habilis? (1) (Homo) ergaster
. The diagram shows an evolutionary tree for humans based on a study of fossils. Homo erectus fossils found in other parts of the world (allow only 50 fossils found in China) (too many) gaps in fossil record Homo erectus on different branch of tree orno evidence of other humans developing from Homo erectus orno link shown between Homo erectus to Homo sapiens / modern humans allow diagram shows they are not closely related or(fossils show that) H. sapiens evolved from H. heidelbergensis/ H. mauritanicus/ H. ergaster (d) About 250 fossils of Homo erectus have been found. About 50 of these fossils have been found in China. A Chinese scientist has suggested the hypothesis that Chinese people evolved from Homo erectus. Most scientists do not agree with this hypothesis. Use the information above and information from the diagram to suggest two reasons why. (2)