01.09.2014 Views

Boyer diss 2009 1046..

Boyer diss 2009 1046..

Boyer diss 2009 1046..

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Specimens included for direct comparison and contrast include those of the<br />

plesiadapiforms Carpolestes simpsoni (UM 101963 and USNM 482354), Ignacius<br />

clarksforkensis (UM 82616), and Ignacius graybullianus (USNM 421608 and USNM<br />

482353); the fossil euprimates Adapis parisiensis (MaPhQ 33y) and Leptadapis<br />

leenhardti (YPM-PU 11481); and the extant rodents Lagostomus maximus (AMNH<br />

41527, 41522), Dipodomys heermani swarthi (AMNH 124181, 39836, 121077), and<br />

Sciurus carolinensis (SBU MRd-12).<br />

Methods of examination and documentation<br />

Specimens were studied under a binocular light microscope. Sutures and cranial<br />

foramina were identified by comparison to extant and fossil skulls. Morphology was<br />

photo-documented using a Nikon Coolpix 4500 camera mounted on a copy stand or<br />

tripod. For more detailed morphology, I used a continuously-calibrated (for pixel scale)<br />

digital camera mounted on a steREO Discovery V12 Zeiss microscope with a 0.63x<br />

objective lens and 10x ocular lens, motorized focus and zoom, and capacity for reflected<br />

and transmitted illumination of objects in the object field (maximum = 36.5mm) via two<br />

Zeiss LCD 2500 light boxes. Measurements were taken from the resulting photographs<br />

(on structures such as cranial foramina) to the nearest hundredth of a millimeter using the<br />

measurement software Axiovision 4.4. In some cases, for specimens that could not be<br />

imaged with the Zeiss microscope, camera lucida drawings of minute morphological<br />

features were made and measured. Prior to photography for documentation purposes,<br />

specimens were whitened with ammonium chloride salt or magnesium powder to remove<br />

tonal contrasts due to the mottled coloration of the fossil or glare off the surface. After<br />

30

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!