Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Evolution of a Kangaroo

By Anthony Kamleh 10BA

Anthony Kamleh

on 13 September 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Evolution of a Kangaroo

Evolution of A kangaroo By Anthony kamleh 10BA The kangaroo or the Macropus, which means big foot, is a marsupial that habits the land of Australia. There are many types of kangaroo, the red kangaroo, eastern grey kangaroo, western grey kangaroo, plus many more. Because they are marsupials, the females have a pouch, were there premature joey stays in until it is ready to leave. A unique feature to a kangaroo is their hopping ability, it is the main form of transportation. They are grazers meaning they would eat grass and shrubs. The Kangaroo Unlike many land animals, kangaroos do not in fact walk, they hop as their means for transportation. Hopping is a lot more efficient then walking, how efficient you may ask? Well an average human can jump approximately 2.1m, a kangaroo can do 7m with ease. The speed they reach can be close to 70km/h, and they seem to hop for a long time without getting as tired as most animals would get. The secret is the leg it self. The muscle used for the Kangaroo to jump has evolved to be elastic like, so they reuse most of their energy when hopping. Their tail also helps give more power to their step, it is used like a lever, giving them balance, support and power sot they can use it for their next hop. For a Kangaroo it is better for it to hop faster, and hope longer, they would reuse most of their energy to jump, so the more they jump the more they reuse their energy. Hopping Evolution of the Kangaroo Megazostrodon 200 million years ago The megazostrodon is commonly believed to be the first mammal on earth, it lived around 200million years ago, near the end of the age of the dinosaur. This creature was shrew/weasel like, and is widely considered the common ancestor for mammals. It was incredibly small, only 10-12cm long and ate invertebrates, and small lizards. Nambaroo 50-25 million years ago It is hypothesized that animals didn't appear the way they did instantly, but started out around 3.45 billion years as a single celled molecular organism, and slowly and gradually evolved via natural selection to get the diverse range of flora and fauna that this Earth inhabits currently, and these flora and fauna will slowly continually evolve. Hypothesis Intelligent design. Other hypothesis It is hypothesized, that every flora and fauna was designed to be the way they are now. Like a watch, masterly crafted at the front, but once it is turned, the interior is shown and the mechanics become visible, which means that it is designed since it runs well. Creationism It is hypothesized for every living or non living thing and the universe it self was created by a higher being around 10,000 years ago. Intelligent design Criticism A major flaw in this is if flora and faunas were intelligently designed, why do animals have it's flaws and inconvenience. Take the giraffe for example and it's laryngeal nerve. This nerve travels down it's huge neck and make and arch back up to get to the other side of the bone, and the distance between the start and end point of this nerve is extremely close, while this nerves takes a long route of approximately 6m in giraffes. If intelligent design was at play, the laryngeal nerve would've taken the short way instead of the long way. Creationism Criticism One of creationism biggest flaws is its simplicity, according to the bible the world was created in 7 days, which compared to what the world is currently date to be, 3.85 billion years, is very underwhelming. Another flaw is also how old the world is supposed to be. According to creationism, the world should be only 10,000 years old is is relatively new, while geological evidence states otherwise. Also Creationism has no scientific evidence to back it up. The story of creation in the book of Genesis was written a long time after the story has been passed down from generation to generation, meaning it is not very accurate. Another reason is this theory was created before the age of modern science, which again states there isn't a lot of scientific evidence Evolution theory Criticism While evolution theory is written off as one of the most scientifically supported theories and many hardcore scientist consider it fact, it still contains some flaws. There are a lot of gaps missing, there are time periods were there are no evidence of animals existing back then, but some may argue that the conditions weren't right for a fossil to be maintain. A common claim by creationist is that evolution has never been observed, meaning, how on earth did one animal turn into a another? Unlike modern kangaroo's, the nambaroo was a meat eater, it was vicious and dangerous. It was dog like, and unlike the kangaroo, it walked on all fours. It had canine teeth at the front, which is a lot different from the rat like teeth at the front on the kangaroos mouth. It is suspected to have opposable big toe which suggest a climbing ability since Australia was a rainforest back then, either to hide, or eat fruit and fungi off trees. Notice how the nambaroo (left ), had a canine looking face, compared to the kangaroo, (right). Ekaltadeta 25million-50,000 years ago The Ekaltadeta, was an omnivorous marsupial, it was very rat like, but also a giant, it was a lot bigger then a modern kangaroo and a modern kangaroo was bigger then a nambaroo. An interesting thing about this creature, is that it's skeletal structure, especially near the leg, looked like an early form of the version modern kangaroo, and some scientist speculate that it could have been the first kangaroo ancestor to be partially hopping, as the nambaroo wasn't. Simosthenurus ~50,000 years ago The simosthenurus, was a large marsupial related to the kangaroo, it stood over 1.8m tall and weighed 118kg. It was almost hopping like the way modern kangaroo's do, buts it's leg still needed more length and elasticity, it had a similar diet as well, consisting of grass and shrubs, which was unlike the Ekaltadeta, since the Ekaltadeta was omnivorous. A reason why for the switch of diets which lead to the way kangaroos are now, was Australia was almost a desert, it was close to a forest, which means there were different food, and the best thing around would've been the shrubs, which is the reason why modern day Kangaroo developed a way to use less energy in their movement and also their way of eating Simosthenurus (Right), Kangaroo (left). Procoptodon 30,000-18,000 years ago The procoptodon can closely resembles a kangaroo in nearly every war, it was a full fledged hopper. It was a giant, standing 2m, and weighing 230kg. It moved fast, like a modern day kangaroo and had the same diet. One thing very different to the Kangaroo was it's toes and paw. It's toes resembled a horses hoof, and it's paws had 2 fingers and claws which was believed to have been used getting down branches from trees. Sexual selection A major characteristic about a Kangaroo, especially the male ones, is there sheer size. It all has to with sexual selection. Male kangaroo usually fight for females and mating rights, meaning the strongest and fittest would be able to spread the gene pool, which is one of the main reason animals only exist for, to reproduce. If the strongest, biggest and fittest get to mate, their child would most likely be the same. And that is one explanation of a kangaroo's size. Convergent evolution There are striking resemblance between, a deer and a kangaroo, one explanation maybe when there was a large super continent,Pangaea, they may have had a common ancestor. But one of the most believed theories is of convergent evolution, when two animals have similar features without having a common ancestor but only because they had a similar environment. When the europeans came, they thought the Kangaroo was the Australian version of the dear. Many scientist believed kangaroos could've been galloping creatures like the deer. They had very similar diets and the facial features strike a remarkable resemblance It is widely believed when the earliest form of marsupials were migrating across Pangea, they were in Australia when the super continent started to break off. There were no other placenta mammals in Australia, meaning they could get most of the food and habitats. The common ancestor of marsupials when through a biological phenomena called adaptive radiation, were animals would evolve from a common ancestor into something different or to have different features, like what happened with the finches in the Galapagos island. All around the world the placenta mammals were better off then the marsupials meaning they got the food, so most marsupials died out that were not from Australia, and since Australia was an island, other land animals couldn't reach here, meaning Marsupials in Australia were free to evolve into what they needed to. Why is there a high concentration of marsupials in Australia? There is a remarkable amount of evidence to equate that a kangaroo got to the way it is from it's evolutionary heritage. Out of all the theories that are out there, with all the fossil, chemical, and geographical evidence point to evolution. Conclusion Some creationist use Australia as an example because some believe God created these unique creatures for Australia which sort of explains it in a creationist kind of way that why you can't find them outside of Australia.
Full transcript