Fossilrecords provide proof of past occurrences. When these elements arejoined, they show a part of evolution that took place a billion yearsago. Although some artifacts have mission elements, a closeobservation shows that they do not have some features that today’screatures have or such features are more enhanced . For instance,researchers found the bite of a mosasaur on an ammonite fossil.Notably, the bites had marks that are entirely different from thoseof the current mosasaur, indicating that some level of evolution tookplace. A cross-section of an artifact of a duckbill dinosaurMiaiasaura shows that it had a horizontal line. Such a feature couldbe an indication that it had periodic growth as a result ofevolution.
Theanatomical evidence is also significant in showing the process ofevolution took place. There is an anatomical similarity betweendifferent organisms although they do not have the same lifestyles.For instance, although dolphins share the same environment with fish,their semblance is quite superficial as they share many features withplacenta mammals such as lungs (Dobzhansky, 2013). Also, young onesof dolphins are gestated internally.
Anotherfeature that exhibits anatomical evidence is the tetrapod limbs thatare shared by many classes of animals such as mammals, amphibians,reptiles, and birds. Notably, this feature shows that livingorganisms share the same origin only that some form of evolution madesome to develop different features from others.
Didyou have any images, or other visuals, to share related to yourexamples of the evidence for evolution? The instructions asked forvisuals and I want to make sure you didn`t overlook that requirementor experience some technical difficulty posting them.
Whatdo you think about the gaps in the fossil record? Is this evidencethat evolution might not be true? How do fossils form? Do all livingthings form fossils when they die?
Hereis a video that uses the example of aquatic mammal evolution todiscuss the evidence for evolution. I`d be curious to know what youfound most interesting from watching the video.
Theexisting pictures help us to easily understand the concept ofevolution. One of the most forms of evolution which have been widelydescribed is the evolution of man. There are several studies thathave been done to explain the evolution of man. The existing pictureshelps us to easily draw the comparison between man and monkey. Thepicture below helps us to see the closeness between man and monkeys.
Visualevolution of the human beings. (“Visual Evolution,” n.d.).
Thegaps in fossil records are too big causing a lot of questions aboutthe evolution theory. First, they do not have an origin. Most fossilsfound are associated with a certain number of years in the past.However, they do not explain where the animals had originated from.This is a major blow to evolution theories since people cannotbelieve them if they cannot explain the source. For example, in theevolution of man, it is said that man evolved from monkey. It ishowever not explained where the monkeys came from. Such gaps makeevolution to appear unreal.
Fossilsform from the hard parts of the body which do not decay easily. Theseare especially the hard bones. Not all the living things formfossils. Scientifically, plants are classified as living things. Whenthey dry, they decay completely and thus no fossils are formed fromthe plants. Animals without hard bones also do not form fossils.Insects and other smaller animals decay completely when the die andthus they do not form fossils. This makes the use of fossils hard anduntrustworthy since a lot is not explained.
Thevideo shows that most of the water animals are similar in very manyaspects. It is very interesting to know that the fish are the basisof evolution. From fish, some organisms evolved to amphibians. Fromamphibians, they evolved further to reptiles and later some evolvedmammals. This is the reason why most of the water animals, althoughvery different, they share most characters. For instance, thehippopotamus and the whale share a lot of amazing characters. Fromthe way they breathe to the way they breed.
Iwas unaware that dolphins had lungs like other mammals. Did you knowthat dolphins fins have the same bones as humans have in their armsand hands?
Dolphinsare amazing animals. Although they stay in the water like fish andtheir body physically resembles some species of fish, it is veryinteresting to learn that they breathe through lungs but not gillslike fish. They however do not have a nose like other mammals, theytake air in and out through the blowhole.
Itis also very interesting to learn that the fins of the dolphinresemble the hands of people. They have exactly the same number andtype of bones. The arrangement of the bones in the fins of thedolphin also resembles that of the human arms and hands.
Greatexample with the dolphins, its really interesting to think of them asmammals. This could be a huge argument for those who believe in ahigher power. If evolution is the cause what did they evolve from andhow did their anatomy adapt so well with their environment!
Althoughdolphins stay in the water like fish, they are mammals. They havelungs like other mammals and do not use gills like fish. They arevery similar to the whales they share very many characters includingtheir habitat. Their similarity with other mammals however does notexplain their origin. Although they resemble the fish, it is easy toprove that they did not evolve from the fish.
Thetheory of evolution does not explain from what animals the dolphinmay have evolved from. It only shows its similarity with otheranimals but this is not a guarantee that it evolved from theseanimals. All animals are well adaptive to their surroundings. Theiranatomy id meant to help them adapt to their new environment. Thismeans that an animal cannot evolve from one surrounding to produce ananimal which lives in a different environment. For example, it is notpossible for the fish to evolve to become hippopotamus.
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Scientistshave found that the embryos of many different species show varioussimilarities which implies that they share a common origin andsupports evolution. An example of this are fish and human embryosboth have gill slits that disappear before birth. Another example isthat ape and human embryos have a tail structure that is also lost bythe time of birth. Also unrelated animals like the arctic fox and abird called a ptarmigan have white phenotypes during the wintermonths to blend with the snow and ice and protect them frompredators. The one that I had never heard of and found interesting isthat snakes and whales have pelvic elements during development. Theseexamples suggest that even though the adults forms are different,various species share a common ancestor.
Somekinds of RNA can activate chemical reactions, meaning that RNA canboth store genetic information and cause the chemical reactionsneeded to copy itself. Another line of biochemical evidenceoccurring in our own cells, in the cells of a fungus, and in abacterial cell are largely different from one another, yet are verymuch alike and rely on the exact same molecules. These molecules suchas ATP, are critical to all life and are thought to have arisen veryearly in the history of life and are nicknamed `molecular fossils`.The discoveries of catalytic RNA and of molecular fossils closelyrelated to nucleic acids suggest that nucleic acids (specificallyRNA) were crucial to Earth`s first life supporting the theory thatearly life used RNA for basic cellular processes, instead of the mixof RNA and DNA used by modern organisms.
Allthe features of animals are to help them to survive in theirenvironments. Every body part has a particular function. This meansthat animals living in the same environment are most likely to havesimilar appearances or structure. Also parts used for the samepurpose are likely to be similar. For instance, the pelvic elementsof snakes and whales are used to help them in movement. Since theirmovement is the same, then the structures are likely to be the same.This means that if animals have similar structures, it is notguaranteed that they share a common origin.
RNAsplay a particular role of copying DNA and ensuring that an animalmaintains its traits. RNAs have been in existence for a long time.This may be an indication that animals have maintained their traits.The changes in the RNAs may just have occurred to help animals toadapt to their environments.
Fossilsprovide solid evidence of evolution. There are examples ofintermediate species that show the transition from the Eohippus from45 million years ago to the modern horse. The transitional fossilsshow the changes in the teeth and body to adapt to their environmentto make grazing easier and the adjustment in the skeletal structureto run from their predators.
Thereis also a lot of fossil evidence concerning the elephant. Elephantsbegan as a smaller animal that was trunk less and had shorter legsfor grazing from the ground. This was 38 million years ago. Overtime they got a little bigger and the trunk developed for grabbingleaves of taller trees. From there the species of elephant developedtusks, more height and a longer trunk including the Mammoth, Mammut,Stegodon and the Anancus (now extinct), and the modern elephants weknow today of the Asian and African elephant that are massive.
Biogeographyis another piece of evidence that we see similar animal in differentplaces. This suppose Pangaea or when all the continents were one bigcontinent. As Pangaea broke up, species could no longer migrate andthen adapted to their environment. A wonderful example of this isAustralia. There are creatures found nowhere else, except inAustralia. There are similar animals on the other continents thatare related but since the species on Australia were separated andisolated they developed very differently from their predecessors. The ostrich is a good example of this. There are similar animals tothe ostrich has similar cousins like the rhea in South america, theEmu in Australia and the Cassowary in Papua New Guinea. Each animalhas characteristics that make it unique but they are all very large,flightless birds. Camels are also a part of this species spread. The Bactrian Camel (2 humps) lives predominantly in Asia, while theDromedary lives in Africa. Because of the desert environment, theyhave the humps that store water so they may survive without water fora time. the Bactrian may have developed the 2 humps because living inthe middle east, there is little water to come by and the daystemperature reaches over the 100`s. Meanwhile, the camels cousins,the llama has no hump and lives in South America.Differentenvironments allowed for them to adapt differently. This furtherproves Pangaea cause species to be apart and yet develop differentlyaccording to their environments.
Animalsmay at times undergo some changes to completely fit in theirenvironment. The conditions of the earth such as climate and foodavailability for animals keep changing. The animals may change theirbody forms to adapt to these changes. If evolution is used to explainthese changes, then it can be true to that point. However, evolutioncannot be used to explain the origin of the animals. The fossilsobtained may not be true at times. For instance, the fossilscollected for elephants showing that they were smaller animals in thepast may have been collected for a young elephant but not a matureone.
Thedistribution of animals may have occurred naturally due to the searchof food and other animal necessities. Animals may have crossed todifferent areas and if they belonged from the same origin, they mayhave common traits. The animals may have undergone some changes tohelp them to adapt to the surroundings.
Dobzhansky,T. (2013). Nothing in biology makes sense except in the light of evolution. Theamerican biology teacher, 75(2),87-91.
VisualEvolution. (n.d.). Retrieved fromhttp://www.creation-vs-evolution.us/visual-evolution/