Hi,

I have two questions that I'm working on that I just can't seem to find a proper answer for no matter how long I search. :confused:


1 The preservation of fossils in any particular location is dependent on many factors. These factors can be of a geological/physical or biological/chemical nature.

Describe any two factors from each group (i.e. geological/physical or biological/chemical) that will influence the presence and/or preservation of fossils.




2 Evolution is the concept that living organisms have changed in some manner over time.

Choose any ONE Class of Vertebrates and:

(I) State the geological time range over which they have existed.

(ii) List at least two examples of organisms which belong to the class.

(iii) For the class of vertebrates that you have chosen, briefly document at least one significant evolutionary change which has occurred that distinguishes that class from other classes of vertebrates.

I have chosen reptiles for Q2 but am open to other suggestions.

Regards
John

John,
Have you looked at Wikipedia? I believe you'll find all your answers there (as well as in any introductory college biology textbook).

1. Fossil - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Fossil#Rarity_of_fossils)

2.Reptile - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Reptile#Evolutionary_history)

Hi,
Thanks for that.

We are for whatever reasons discouraged from using Wikipedia as much as possible because there is so much wrong information inserted, and for the unknowing like me it's kind of hard to tell one from the other, sad isn't it. :) That's not to say of course that I still don't use it because it does just simply have so much info in the one place.

I have handed up my assignment and had an OK result but the first part of that question was a bit confusing.

Anyhow thanks for your help, much appreciated.

Cheers
John

You are welcome!

A study by Nature (a science journal) found that Wikipedia had very few more errors in it than the encyclopedia britannica. If you are reading something controversial, you might find some vandalism, but Wikipedia contains a huge amount of accurate information. Also, at the bottom of each page is often a list of references. These can be useful. It's unfortunate that your teachers are so afraid of Wikipedia. Using the internet means, in part, being able to recognize information that is reasonably authoritative (or obvious hoakum).

As far as the question. Anything hard, like bone or shell, can be preserved because it doesn't rot quickly and if buried in mud or sand, it can become fossilized. Something delicate like a jellyfish or a mosquito is MUCH less likely to be fossilized. The fossil record overwhelmingly reflects the history of vertebrate animals (those with bones, skulls, backbones, like ourselves) and also the history of shelled animals such as clams, mussels, and snails.

Also, animals that live in or near water are more likely to be fossilized. The explanation for that would take longer... and I have to get back to work. But hopefully, you get the idea.

Cheers,
asking