We know that dinosaurs once roamed the Earth because we have fossils of these extinct creatures. And we can even tell when by using radioactive dating. But do fossils tell the whole story? What other evidence is used to show us evolution has taken place?Read the following article, Can Modern-Day Plants Trace Their New Zealand Ancestry?. Scientists are trying to trace the evolutionary path of the plants that are on the island of New Zealand. Are the current plants descendents of plants from after Pangea split apart, or are they more recent inhabitants of the island. What evidence was used to support scientist's current hypotheses? What other evidence is used to support evolution? What is wrong with just relying on fossil evidence?
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The article says that evidence presents that these fossils that can trace it back to the time of Pangea. Relying on fossil evidence does not always factor in chance. There are many things that could have changed because it was left up to chance.
ReplyDeleteFossils say that the plant was from the Late Cretaceous period. The fossil record of pollen can be read to say that the Ericaceae plant dates back to the breakup of Gondwana; however, leaf fossils and evidence from molecular biology say the opposite.
ReplyDeleteFossils are mainly used to support evolution. Bones hidden deep within the ground can also be used, as well as possibly mummies (?). Just relying on fossil evidence can be misleading, because you can't see the whole picture from just a fossil.
The fossil record dates the plants back to some 99.6 million years ago, during the late Cretacious period. The scientists have found modern examples of the plant though, by compariong the fossils to other plants that have gone extinct. The problem with dating fossils is the broad time span you have to deal with. The plants were dated between 60-99 million years ago (not exactly specific). If plants being compared went extinct 15 million years apart, they would still be in the same "period", which makes the findings innacurate.
ReplyDeleteTwo macrofossils came from the late Oligocene or Early Miocene time period in New Zealand. They both were members of th epacrid subfamily of the Ericaceae plant family. The pollen from the fossil records did help find out whether the plants in New Zealand were there since the Early Miocene, which they were. However fossils still can't be depended on to discover the whole ancestry or lineage of a plant.
ReplyDeleteAnna, What does chance have to do with fossils? Please explain what you meant.
ReplyDeleteThere is no way to know for sure if they are descendants, because we only know they are from the same time period, but that's it. The evidence they found was the fossils they had found. The problem with relying on fossils is that some have become extinct.
ReplyDeleteFossils can't always give scientists useful information because they are millions of years old. It is not possible for scientists to relate ancient fossils to animals/plants to present day animals or plants. Therefore, fossils can and cannot be useful for scientists. If they want to find out what kind of animals lived millions of years ago, then fossils can help them find that information out. Or if they want to relate the fosslis to present day animals or plants, there is no proof that the information is correct.
ReplyDeleteWhile fossils are intresting and do help scientist and researchers look into prehistoric organisms, fossils are not helpful when relating them with present-day organisms. Fossils are not reliable in giving detail of evolution, but they do give off information on organisms long ago. Scientists such as Dr. Gregory can only guess which plant is a ancestral version of a modern-day plant, making it hard to prove evolution within plants.
ReplyDeleteAfter the spilt of Pangaea, Gondwana divided and part of it is modern-day New Zealand. Dr. Gregory Jordan explores the possibility of fossil’s origins here. These fossils were identified as being apart of the Ericaceae family. By examining these they decided that by the Early Miocene, New Zealand contained at least two different family lines of this species. The fossil pollen may suggest the presence of these fossils date to the Late Cretaceous, but now are suggesting a younger family. Two lineages have turned out to be extinct. Scientists’ logic and data is conflicting on trying to date these fossils. Combined with evolutionary analysis’s may help to answer these questions.
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