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Activity: critical analysis of Archaeopteryx

Some scientists consider Archaeopteryx to be a transitional fossil between dinosaurs and birds. Other scientists disagree. Below are two arguments given by scientists to support their interpretation that Archaeopteryx is not a transitional fossil between dinosaurs and birds. For each of these arguments, state whether the scientists are questioning the DATA, or the CONCLUSIONS about the Archaeopteryx fossil.

  1. Watkins, Hoyle, Wickramasinghe, Watkins, Rabilizirov and Spetner (1985) published an article where they claimed that the feather impressions of Archaeopteryx were forged. They provide evidence suggesting that chicken feathers were pressed into a cement mix, and these were applied over dinosaur fossils: Watkins, R.S., Fred Hoyle, N.C. Wickramasinghe, J. Watkins, R. Rabilizirov, andL.M. Spetner (1985), “ Archaeopteryx : A Photographic Study,” British Journal of Photography, 132:264-266, March 8.

    These scientists are questioning the DATA / CONCLUSIONS made by other scientists about Archaeopteryx .

  2. Some scientists argue that even if the feathers on Archaeopteryx were not forged, there is no evidence that the fossil is transitional between reptiles and birds, since the fossil is compatible with the fossil of a bird.

    These scientists are questioning the DATA / CONCLUSIONS made by other scientists about Archaeopteryx .

  3. Some scientists argue that birds have been found in younger rocks than the rocks in which Archaeopteryx was found, and so Archaeopteryx cannot be the ancestor to birds.

    These scientists are questioning the DATA / CONCLUSIONS made by other scientists about Archaeopteryx .

  1. Data
  2. Conclusions
  3. Conclusions

In 1938, an East London fisherman caught a deep-sea fish he had never seen, so it was taken to the East London museum, where it was identified as a coelacanthby Professor JLB Smith and his assistant, Marjorie Courtenay-Latimer. This caused an international uproar, because the fish was previously known only fromfossils and had been believed to be extinct. People were amazed that fossil coelacanth found in rock strata 70 –350 million years old could look exactly like the large blue fish before their eyes! This started a search for more specimens and 14 years later, another one was caught off the Comoro Islands inthe Indian Ocean, north of Madagascar and more have been found since, including in deep crevices at St. Lucia in northern KZN.

Coelacanth display
Madge Courtenay-Latimer and the coelacanth

Scientists agree that the coelacanth is probably the oldest living vertebrate and they are thought to be closely related to the freshwater fish that is seenas the ancestor of all land animals. The coelacanth’s internal organs are in many ways similar to those of amphibians, which are the earliest life formsto have colonized land. Unlike amphibians, its spine is supported by a permanent notochord, a cartilage and oil tube – it never develops a bony vertebral column like other fish do. The body is lobe-finned, not ray-finned like modern fish,although it is not known to “walk” on the ocean floor. Many scientists had thought that the coelacanth’s fins looked like“legs” (it was referred to as ‘old four legs’) and that it was in the process of developing limbs for use on land, but here was aspecimen, millions of years later, that still had the same fin structure. Its nostrils are also not blind-ending as in fish; they open into the mouth and can be used for breathing.

Assignment:

The modern coelacanth-finding throws doubt on an assumption palaeontologists use when reasoning about what the fossil record says about extinctions.
  1. What is the assumption the modern coelacanth-finding throws doubt on?
  2. How does the modern coelacanth-finding throw doubt on this assumption ?
An extinction event can be recognised by fossils of that type not being found in higher (i.e. younger) rock. Although no coelacanth fossils are found in rock younger than that assumed to be100 million years old, coelacanths are not extinct: they are alive today (extant).

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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why and for what was five kingdom of classification of organisms introduced
SUBHIKSHA Reply
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SUBHIKSHA
Comment on the ozone depletion over the period of 1982 to 1996
Mpho Reply

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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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