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http://www.open.edu/openlearn/nature-environment/natural-history/tree-life
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sexta-feira, 24 de julho de 2015
quinta-feira, 28 de maio de 2015
sábado, 12 de janeiro de 2013
segunda-feira, 13 de agosto de 2012
domingo, 27 de novembro de 2011
domingo, 21 de agosto de 2011
Introduction
"Wallace is one of the most important figures of nineteenth-century biology and in character among its most admirable.
He is also one of the very few, like Darwin and Maxwell, whose importance grows with time." E. O. Wilson
Wallace is on both Facebook and Twitter. Check them out!
By the time of his death Wallace was probably the world’s most famous scientist, but since then his intellectual legacy has been almost completely overshadowed by Darwin’s, largely thanks to the “Darwin Industry” of recent decades. This ‘industry’ has led to a highly “Darwinocentric” view of the history of modern biology, and as a result many of the important contributions made by Darwin’s contemporaries, like Wallace, are currently underestimated and undervalued.
This website is intended to be an island of accurate information in the sea of misinformation about Wallace. It contains information about Wallace's life and work, a unique archive of images, FAQ's debunking some of the many myths surrounding Wallace and Darwin, plus information about the A. R. Wallace Memorial Fund and its projects. Please explore the site by clicking on the links on the menu to the left.
"I am thankful I can see much to admire in all religions. To the mass of mankind religion of some kind is a necessity. But whether there be a God and whatever be His nature; whether we have an immortal soul or not, or whatever may be our state after death, I can have no fear of having to suffer for the study of nature and the search for truth, or believe that those will be better off in a future state who have lived in the belief of doctrines inculcated from childhood, and which are to them rather a matter of blind faith than intelligent conviction." Wallace, writing from the field to his brother-in-law Thomas Sims in 1861 on the subject of belief.
The content on this site was written by evolutionary biologist and entomologist Dr George Beccaloni (aka 'Wallace's Rottweiler'), except where noted. All views expressed on the site are his own. Most of the images on this site are copyright of their creators and may not be reproduced in any form without permission. For more information about reproducing images please CLICK HERE. To email George CLICK HERE.
The site was launched in January 2008 and is maintained by George.
Please feel free to link to any of the site's content.
The Wallace Fish is copyright of Chris Clarke.
Please feel free to link to any of the site's content.
The Wallace Fish is copyright of Chris Clarke.
Common variations of Wallace's name:Wallace; Alfred Wallace; A. R. Wallace; Alfred R. Wallace; Russel Wallace; Alfred Russell Wallace [sic]
quarta-feira, 6 de abril de 2011
terça-feira, 5 de abril de 2011
Ateles paniscus
black spider monkey
Classification
Images
Specimen Code: DKY_1073, Sex: male, Age: -
Measurements (mm) - Maximum Length: 108.2, Zygomatic Breadth: 68.6, Posterior Cranial Breadth: 58.6, Nasion-Basion: 60.8
Measurements (mm) - Maximum Length: 108.2, Zygomatic Breadth: 68.6, Posterior Cranial Breadth: 58.6, Nasion-Basion: 60.8
L
S
Specimen Code: DKY_0649, Sex: female, Age: -
Measurements (mm) - Maximum Length: 108.2, Zygomatic Breadth: 68.6, Posterior Cranial Breadth: 58.6, Nasion-Basion: 60.8
Measurements (mm) - Maximum Length: 108.2, Zygomatic Breadth: 68.6, Posterior Cranial Breadth: 58.6, Nasion-Basion: 60.8
L
S
L: Left, A: Anterior, S: Superior
(To see a large photo, click a picture.)
(To see a large photo, click a picture.)
Crânios de Mamíferos
Mammalian Crania Photographic Archive
Second Edition (MCPA2)
Revised on December 1, 2005
- Browse the Pictures
- Download
- What is MCPA2?
- Overview
- Incentives
- Contents
- Miscellaneous
Feedback to feedback-1kai@dokkyomed.ac.jp
Elephas maximus
Indian elephant
Classification
Images (Go to the List of the Specimens)
Specimen Code: DKY_0853, Sex: male, Age: -
Measurements (mm) - Maximum Length: 754.0, Zygomatic Breadth: 581.0, Posterior Cranial Breadth: 585.0, Nasion-Basion: 420.0
Measurements (mm) - Maximum Length: 754.0, Zygomatic Breadth: 581.0, Posterior Cranial Breadth: 585.0, Nasion-Basion: 420.0
A
S
L: Left, R: Right, A: Anterior, P: Posterior, S: Superior, I: Inferior
(To see a large photo, click a picture.)
(To see a large photo, click a picture.)
The Bison at Ayer Pond on Orcas Island is archaeological.
Cranium of 14,000 year old Bison antiquus from Ayer Pond, Orcas Island, Salish Sea. Source: Kenady et al. 2010 (in press)
For years now, we have known that one of the large land mammal species of the Salish Sea around 14,000 years ago was bison — and not just any bison, but Bison antiquus, the extinct giant bison. A number of remains of this creature have been found, mostly on the Saanich Peninsula and on Orcas Island, which is one of the largest islands in the Salish Sea, sitting just south of Saturna Island, close to the Canadian Border. Since these remains mostly clocked in at around 13,000 to 14,000 years ago, most archaeologists were interested in them primarily for their coolness factor and not because they seriously thought there might be relevance to early human presence here – these bison pre-date the Clovis Culture which was the consensual evidence for the first peopling of the Americas. I have previously posted on this with reference to Clovis in Puget Sound, to the controversial Manis Mastodon site, as well as to the nearby Wenas Mammoth and even the Paisley Cave finds in Oregon – evidence is coming together for both a Clovis and a pre-Clovis occupation of the Salish Sea and environs.
Now with a new paper by Kenady et al. in press, these numerous bison finds take on a new importance: one of them is most likely archaeological.
Bison antiquus (right) compared in size to modern Bison (Bison bison). Source: texasbeyondhistory.net
Now, where the story gets a little unusual is in the story of the discovery. In 2003, some workmen were digging a trench with a backhoe at this pond (which is a partially artficial pond created from wetlands) when they noticed these large bones. Backhoe operators are often keen observers of what comes out of the ground! Remarkably, the operators and drivers stopped work and excavated the site by hand, without tools, finding and collecting 98 bone elements and fragments, including some very small and delicate ones. With the property owners not present, the workers were unsure of what to do, so they stored the bones in a cardboard box, uncleaned and untouched for several years until they came to the attention of scientists. The exception is the skull, which was cleaned and displayed in one of the workers house.
So – the actual excavation of the site was not done by archaeologists, which is sub-optimal. In this case though, it is not fatal to the site interpretation, both because of the careful recovery, and because the uncleaned bones had considerable soil, peat, and other sediments adhering which established their stratigraphic context inc comparison to the pond’s stratigraphy. And while it would have been strongly preferable to document the process of recovery of these bones, the fact is the bones themselves tell the story as much as their relative position or possible associations would have. While some bones may have been missed, subsequent investigation by archaeologists of the backdirt and area did not find any other bones. It seems the workers did a thorough and efficient job working with their bare hands.
Bone preservation is excellent and the surfaces of the bone are not eroded or pitted or otherwise obscured. As the authors explain, the parts of the skeleton present are limited to the cranium and to the lower ends of the limbs, with only one or two minor exceptions such as a single vertebrae. This pattern is most consistent with human butchery.
Spiral fractures and conchoidal percussion on otherwise unmodifed elements from Ayers Pond. Source: Kenady et al. in press (2010).
For example, the above picture shows the left and right distal tibia (the lower end of the hind lower leg bone) of the Ayer Pond bison. Note that these two bones have been broken open in identical ways using percussion, resulting in spiral fracture, and show no signs of carnivore activity. This seems to me to be extremely difficult to attribute to natural agencies.
As importantly as showing the bones at Ayer Pond are consistent with human agency, the authors show they are inconsistent with natural agencies like carnovores or trampling. It must be remembered that the alternative to human agency is not a structureless and ambiguous bone assemblage. Rather, the alternative is a highly, yet differently, structured assemblage bearing the characteristic hallmarks of natural agents such as wolves or even the giant short-faced bear, a mega-scavenger known to be in the area at this time. Since the bones show many signs consistent with human predation and essentially lack any signs consistent with scavenging by animals, both tails of the data spread, positive and negative, need to be considered. There is no other plausible explanation for the appearance and distribution of these bones. The likely scenario is a kill and butchery on the frozen surface of paleo-Ayer Pond, followed by rapid sinking of the unwanted portions of the carcass into the wetland, and hence preservation free from scavenging.
So it is a remarkable find and a careful analysis which seems to me to be quite conclusive, despite the unusual recovery process. Humans were therefore in the Salish Sea by 14,000 years ago and the fact we have not yet found abundant evidence of this is probably mostly due to having looked in the wrong places: a failure of imagination to think of our familiar region at times of different sea levels (see below), as a tundra, as a grassland teeming with giant bison.
Changing sea levels at end of ice age, showing changing configurations of Saanich Peninsula and area. Upper right image is the time of Ayer Pond bison; Orcas Island is partially seen to extreme right in all pictures. Source: James et al. 2009. Click to enlarge.
James, T., E.J. Gowan, I. Hutchinson, J.J. Clague, J.V. Barrie and K.W. Conway 2009. Sea-level change and paleogeographic reconstructions, southern Vancouver Island, British Columbia, Canada. Quaternary Science Reviews: 28 (13-14): 1200-1216
Kenady, S.M., Wilson, M.C., Schalk, R.F., Mierendorf, R.R. in press (2010). Late Pleistocene Butchered Bison antiquus from Ayer Pond, Orcas Island, Pacific Northwest: Age Confirmation and Taphonomy, Quaternary International (2010), doi: 10.1016/j.quaint.2010.04.013
Wilson, Michael C., Stephen M. Kenady and Randall F. Schalk 2009. Late Pleistocene Bison antiquus from Orcas Island, Washington, and the Biogeographic Importance of an Early Postglacial Land Mammal Dispersal Corridor from the Mainland to Vancouver Island. Quaternary Research 71: 49-61.
http://qmackie.wordpress.com/2010/04/24/orcas-bison/#more-2516
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