nemfrog:

Fig. 198. X-ray of a dried skull. The Internal Anatomy of the Face. 1916.

nemfrog:

Fig. 198. X-ray of a dried skull. The Internal Anatomy of the Face. 1916.

(via theolduvaigorge)

corporisfabrica:

Coronal and ventral x-rays of the hammerhead shark, Sphyrna mokarran.

The distinguishing feature of this animal is, of course, the highly unusual skull shape. You may once have wondered what exactly this seemingly clumsy structure contributes to this fearsome predator, and biologists still do. However, a number of theories exist to explain this unique adaptation; here are some of the best:

  1. All the better to see you with: mounting the eyes at either end of the broad skull allows excellent vision in all areas of the vertical plane. Hammerhead sharks, as hunters of bottom-dwelling animals, can use this superior angle of vision to better locate prey. 
  2. Another pair of fins. The head has evolved into the shape of an effective hydrofoil. It is thought that this may provide greater stability to the shark when making sharp turns and hunting.
  3. Heartbeat sensor. Like many sharks, the hammerhead possesses specialised electrosensory organs called the ampullae of Lorenzini. With these, it can detect the magnetic activity of the Earth and find its heading by means of biological compass. Much more impressively, the hammerhead can detect the minuscule electrical activity emitted by the muscle contractions of its prey, allowing location even when hidden from sight. Almost like a skull-mounted metal detector, the shark may sweep the seabed. All it takes is a heartbeat to give the game away. 

Photo credit to Dan Anderson.

westerndigs:

At the bottom of a sinkhole as deep as an eight-story building, paleontologists have recovered the remains of giant camels, American lions, dire wolves and a cheetah-like big cat, among other finds. And, the scientists say, many of the specimens still have their DNA intact — an unprecedented trove of genetic information from America’s extinct animals. Read on to see more!

(via ancient-anthropoids)

Virtual Fossils

palaeoanth:

image

Homo erectus. Sambungmacan 3.

image

Homo ergaster. OH 9.

(via theres-blood-in-the-water)

theolduvaigorge:

The human hand has hardly changed in the past million year
from CENIEH
“Adrian Pablos, from Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) and the Universidad de Burgos (UBU) es is coauthor of a study, published in the Journal of Human Evolution, about the Early Pleistocene hand phalanx (ATE9-2) from the Sima del Elefante in Atapuerca, (Spain), ascribed to Homo sp., which was found in 2008, which evidences that hand morphology has hardly changed since 1,3 million yeras ago.
In this study, a new Early Pleistocene proximal hand phalanx (ATE9-2) from the Sima del Elefante cave site (TE – Sierra de Atapuerca, Spain), ascribed to Homo sp., is presented and comparatively described in the context of the evolution of the genus Homo.
The ATE9-2 specimen is especially important because of the paucity of hand bones in the human fossil record during the Early Pleistocene. The morphological and metrical analyses of the phalanx ATE9-2 indicate that there are no essential differences between it and comparator fossil specimens for the genus Homo after 1.3 Ma (millions of years ago).
Similar to Sima de los Huesos and Neandertal specimens, ATE9-2 is a robust proximal hand phalanx, probably reflecting greater overall body robusticity in these populations or a higher gracility in modern humans. The age of level TE9 from Sima del Elefante and morphological and metrical studies of ATE9-2 suggest that the morphology of the proximal hand phalanges and, thus, the morphology of the hand could have remained stable over the last 1.2–1.3 Ma” (read more).
***Haven’t read it. Does irreverentideas have any thoughts?
(Source: CENIEH)

Thoughts: 
This is a really cool addition to our short list of manual remains but it is too little to draw such a dramatic conclusion about. The authors do make an attempt to combine their observations with the VERY modern looking 1.43 million year old 3rd metacarpal (Ward et al. 2014), which is does support their conclusion. If we think about the bones in the hand where we would expect a dramatic change over 1,3 million years of tool use, the 5th proximal phalange would be somewhere on the bottom of the list.  
Those at the top of the list include the carpals, and the bones of the thumb. In fact that is where we do see major muscoskeletal reconfiguration when we compare the hands of Neanderthals and AMH. This sounds circular, but the function of the phalanges are really just a series of levers that more or less move in a single plane. The only dramatic change that we might expect is in the length and breadth of the lever (like we see in chimpanzees/gorillas/orangutans/gibbons) along with some adjustments at the base/head for fractional adjustments in rotation and stabilization.
The carpal/metacarpals, however, have to deal with the displacement of loads and a much more sophisticated range of movements. Although I fully subscribe to the neutral theory, I do believe selection has acted on the morphology of these bones and, as such, I find them to be much more convincing lines of argument for the stabilization of manual morphology.
Despite my reservations, I do believe that Lorenzo et al. are correct. Mainly because I suspect that they have access to an array of fossils that are yet to be published, and that I have not seen. So, stay tuned, I suppose. 

theolduvaigorge:

The human hand has hardly changed in the past million year

  • from CENIEH

Adrian Pablos, from Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) and the Universidad de Burgos (UBU) es is coauthor of a study, published in the Journal of Human Evolution, about the Early Pleistocene hand phalanx (ATE9-2) from the Sima del Elefante in Atapuerca, (Spain), ascribed to Homo sp., which was found in 2008, which evidences that hand morphology has hardly changed since 1,3 million yeras ago.

In this study, a new Early Pleistocene proximal hand phalanx (ATE9-2) from the Sima del Elefante cave site (TE – Sierra de Atapuerca, Spain), ascribed to Homo sp., is presented and comparatively described in the context of the evolution of the genus Homo.

The ATE9-2 specimen is especially important because of the paucity of hand bones in the human fossil record during the Early Pleistocene. The morphological and metrical analyses of the phalanx ATE9-2 indicate that there are no essential differences between it and comparator fossil specimens for the genus Homo after 1.3 Ma (millions of years ago).

Similar to Sima de los Huesos and Neandertal specimens, ATE9-2 is a robust proximal hand phalanx, probably reflecting greater overall body robusticity in these populations or a higher gracility in modern humans. The age of level TE9 from Sima del Elefante and morphological and metrical studies of ATE9-2 suggest that the morphology of the proximal hand phalanges and, thus, the morphology of the hand could have remained stable over the last 1.2–1.3 Ma” (read more).

***Haven’t read it. Does irreverentideas have any thoughts?

(Source: CENIEH)

Thoughts: 

This is a really cool addition to our short list of manual remains but it is too little to draw such a dramatic conclusion about. The authors do make an attempt to combine their observations with the VERY modern looking 1.43 million year old 3rd metacarpal (Ward et al. 2014), which is does support their conclusion. If we think about the bones in the hand where we would expect a dramatic change over 1,3 million years of tool use, the 5th proximal phalange would be somewhere on the bottom of the list.  

Those at the top of the list include the carpals, and the bones of the thumb. In fact that is where we do see major muscoskeletal reconfiguration when we compare the hands of Neanderthals and AMH. This sounds circular, but the function of the phalanges are really just a series of levers that more or less move in a single plane. The only dramatic change that we might expect is in the length and breadth of the lever (like we see in chimpanzees/gorillas/orangutans/gibbons) along with some adjustments at the base/head for fractional adjustments in rotation and stabilization.

The carpal/metacarpals, however, have to deal with the displacement of loads and a much more sophisticated range of movements. Although I fully subscribe to the neutral theory, I do believe selection has acted on the morphology of these bones and, as such, I find them to be much more convincing lines of argument for the stabilization of manual morphology.

Despite my reservations, I do believe that Lorenzo et al. are correct. Mainly because I suspect that they have access to an array of fossils that are yet to be published, and that I have not seen. So, stay tuned, I suppose. 

(via anthrogirlet)

theolduvaigorge:

School of Anthropology and Conservation, University of Kent

June 24-26 2015

"The School of Anthropology and Conservation at the University of Kent, Canterbury is hosting a three-day interdisciplinary conference on "The Anthropology of Hands”.   This is an open call to submit abstracts for presentations (podium or poster) at this unique event. The deadline for abstract submission is September 17, 2014 (see abstract guidelines below).

Human hands function as interactive links to the world around us. Hands serve human life: to feed, to communicate, to nurture to work in the broadest sense. In this conference, we aim to map what is known of hands from human evolution and biology, to human communication, to “the world at hand” from both biological and social anthropological perspectives, as well as other disciplines. We ask questions such as: How are human hands different from those of other animals?  How did human hands evolve? How do our closest living relatives the other great apes use their hands? How do hands function biomechanically? How is handedness linked to brain morphology and language development?  Is the first language of humans one of gesture? How do hands represent human presence in cave art and body paint?  How does the hand feel the world around it? What feeling/emotion is there in touching?  Do we think with our hands?  How are hands used as metaphors in everyday life? How is our world influenced by right and left hand symbolism? Is the world just beyond our hand part of our mind?  What is the role of hands in human labour, and what are the consequences of their supplanting by mechanized production? In pursuing a broad understanding of human hands, we aim to turn anthropological analysis back to its long desired yet postponed universalist and interdisciplinary paths” (read more).

(Source: University of Kent via @irreverentideas on Twitter)

ifimeanalottoyou:

Drugs Under The Microscope

(via the-anti-anthropologist)

Going open access. 

Going open access. 

malformalady:

Black Obsidian skull. The skull is 5.3 inches long from front to back, it has a moveable jaw, and all the teeth are made of Australia opal.

malformalady:

Black Obsidian skull. The skull is 5.3 inches long from front to back, it has a moveable jaw, and all the teeth are made of Australia opal.

(via paintedfoxx)

ronbeckdesigns:

Hand Artery Map | unknown

ronbeckdesigns:

Hand Artery Map | unknown

(via valdanderthal)

mydeadthingsdiary:

Primate skulls [x]

(via paintedfoxx)

theolduvaigorge:

How to build a Neandertal

Fossils from Sima de los Huesos show a mixture of Neandertal and more ancient features

  • by Jean-Jacques Hublin

"Under a desolate sierra of northern Spain, in the darkness of a deep shaft, lies the largest accumulation of hominin fossils ever found. On page 1358 of this issue, Arsuaga et al. (1) date this paleontological treasure at the Sima de los Huesos (see the photo) and shed new light on one of the most impassioned issues in the field of human evolution: How did Neandertals evolve? Four to five hundred thousand years ago, archaic humans in western Eurasia diverged from other groups of that period in Africa and eastern Asia. Their skull, jaw, and teeth began to display features that characterize later Neandertals. When modern humans— which had evolved in Africa—finally colonized Eurasia 50,000 years ago, they occasionally interbred with local Neandertals, but the two groups already showed some signs of reproductive incompatibility (2). The extent of their morphological divergence over such a short period of time is striking (see the figure). Polar bears and brown bears provide another example of rapid divergence over a few hundred thousand years (3). However, other sister species have stayed quite similar for much longer periods of time (see the figure), and among mid-sized mammals, complete reproductive isolation generally takes at least 1.4 million years to develop” (read more/open access).

(Open access source: Science 344:1338-1339, 2014 via Academia.edu)

Tags: Because JJ

valdanderthal:

Cutaway mandible showing developing dentition 
-France, D. (2009). Human and Nonhuman Bone Identification. CRC Press.

moshita:

stone carved bone sculptures

Stephen Shaheen 

(via theres-blood-in-the-water)