Ahh, well, Richard, it's gallant of you but of course you don't have to
come to the defense of anyone, because no one has been attacked.

I probably did fail to make myself clear, however. The tooth in question
was a human second lower molar or m2. In my conversation with the
'confused' person, I was not speaking from some old-fashioned theory of
the evolutionary origin of that tooth, or any tooth, but merely stating
the correct fact that this tooth is one of two in each rear quarter of the
human jawbone that are not replaced. It therefore can in no sense be
"deciduous". To repeat: there is no such thing as a "deciduous molar"; it
is impossible by definition, because the only deciduous teeth are by
definition premolar, canine, or incisor teeth. That the tooth in question
is not replaced -- in other words, it develops in and erupts from a
'one-tooth alveolus' -- is what defines this tooth as a molar in the
technical (as opposed to the vernacular) sense.

Your response prompted me, of course, to go back to my library to check a
reference or two, and the happy result is that I am able to report an
error on p. 46 of the otherwise very helpful book "Teeth" by Simon Hillson
(Cambridge Univ. Press). The error is in Fig. 1.25, which shows deciduous
and permanent teeth in Homo. The error is that the labels for the lower
teeth have been switched -- i.e. the label that says "permanent lower"
actually shows the deciduous lower arcade. The labels for the deciduous
and permanent upper arcades are correct.

The tooth formula given on p. 44 of this book for humans is correct:

di2/2, dc1/1, dp2/2 ----> i2/2, c1/1, p2/2, m3/3

....and this is what, as I said before, I was trying to help my physical
anthro colleague to understand. Also as I said before: I sympathize, it is
easy to get mixed up. -- Dr. Deb



> This is off topic, but let me come to the defence of the  physical
> anthropologist that Deb conversed with.
>
> The anthropologist spoke of a human tooth as a 'deciduous molar'.
>
> Deb says she told the "confused" anthropologist that there are no
> deciduous molars.
>
> In saying this, Deb is following the evolutionary position that the two
> human molariform teeth are adaptively evolved from premolars.
>
> I want to make the point that the physical anthropologist, in terms of
> nomenclature, was by no means confused. She is in step with functional
> terminology widely used by English speaking physical anthropologists -
> and dental anatomists, clinical dentists, orthodontists, etc..
>
> The two deciduous grinding teeth are called 'molars', whatever the
> evolutionary origin of these molariform teeth might be.
>
> Richard
>
>
> On 5/10/2012 05:58, [log in to unmask] wrote:
>> [snipped]
>>
>> I go into this a little because it's a subject dear to my own heart; I
>> am
>> currently writing a textbook on equine dentistry, which I have been
>> researching for years. I have a great admiration for all
>> zooarchaeologists
>> but I also know, from talking with some anthro/archaeo graduates, that
>> they can be mixed up about some things. For example recently I had to
>> demur (for the sake of peace) in a conversation in which someone trained
>> in physical anthropology insisted to me that a certain human tooth
>> represented a 'deciduous molar'. She is confusing 'molar' in the sense
>> of
>> 'cheek tooth' with 'molar' in its technical sense, i.e. molar vs.
>> premolar. When I told her there are no deciduous molars, that only the
>> premolar teeth are replaced, or again that there are 'one-tooth alveoli'
>> vs. 'two-tooth alveoli', she was surprised and confused because she also
>> has muddled the term 'pre' in 'premolar', confusing 'pre' meaning
>> anterior
>> in TIME with 'pre' meaning anterior in POSITION. I sympathize; it is
>> easy
>> for anyone to get mixed up when the information presented in most
>> existing
>> textbooks fails to convey an adequate mental picture. -- Dr. Deb
>>
>>
>
>
>