ANT 3514- Introduction to Biological AnthropologyPlio-Pleistocene HominidsLab 9, Week of 3/14/05The focus of this lab is gracile and robust Australopithecines and “early Homo”. As such,we will be comparing specimens of the subfamily Australopithecinae with those of the early members of the subfamily Homininae. The genus Homo emerges approximately 2.4 m.y.a., and as we will see these fossils possess both ancestral and derived morphological traits. STATION 1 – Gracile vs. Robust “Australopithecines” (pgs. 213-216, 218, 228, and 245 in your textbook)This station focuses on the similarities and differences between the gracile and the robust Australopithecines. At this station you will find:- Composite cranium of Australopithecus afarensis - 2 crania of Paranthropus robustus (A6, A28)- a mandible of Paranthropus boisei (“Peninj”)- 2 crania of P. boisei (KNM-ER 406 and OH 5)- a cranium of Paranthropus aethiopicus (KNM-WT 17000 – “The Black Skull”)The subfamily Australopithecinae (the Australopithecines) contains a gracile group and a robust group. These groups are differentiated based on differences in their cranial morphology. (Their postcrania do not necessarily conform to a “gracile vs. robust” distinction.)(in class) Complete the following table comparing the crania of these different australopithecines:A. afarensis P. robustus P. boisei P. aethiopicusCranial cresting (sagittal and nuchal)Degree of PrognathismDegree of Post-Orbital ConstrictionSize of anteriorvs. posterior teethOverall Robusticity(rank 1=most robust, 4=least)(at home) What do the cranio-dental differences between the species noted above suggest to you about the subsistence strategies of robust and gracile Australopithecines?STATION 2 – Australopith Mandibular Anatomy(in class) Compare the mandibles of each species:A. afarensis P. boisei Pan troglodytes H. sapiensDental Arcade Shape (rectangular vs. U-shaped vs. parabolic)Canine Size (small vs. large)P3 form (1 or 2 cusps)Presence/Absence of ChinSTATION 3 – Gracile Australopithecines and HomoThe focus of this station is to compare the differences between the gracile australopithecines and Homo habilis. At this station you will find:- a cranium of (A73)- a cranium of Homo habilis (KNM-ER 1813)- A. africanus foot- femur of H. sp. (KNM-ER 1481)- articulated foot and a femur of a chimpanzee- human femur(in class) List any post-cranial features from the H. habilis foot and H. sp femur that indicate bipedality. Use human and chimpanzee material for reference.(in class) Complete the following table regarding the similarities and differences between the H. habilis and A. africanus crania:A. africanus H. habilisCranial Vault Height(short vs. tall)Overall Robusticity(most vs. least)Degree of PrognathismShape of Face/ Zygomatics(flared vs. non-flared; broadvs. narrow; tall vs. short)Dental Arcade Shape(U-shaped vs. parabolic)(at home) Can A. africanus conceivably be ancestral to H. habilis? Why or why not? Include morphological (from the specimens) as well as temporal and geographic elements in your answer. Reference boxes 6-2, 7-3, and 8-1 to support your answer.STATION 4 Robust australopithecines and HomoThe focus of this station is to compare the crania of the robust australopithecines and early Homo. At this station there is:- crania of P. boisei (A27, A30)- a cranium of Homo habilis (OH 24)- a cranium of Homo rudolfensis (KNM-ER 1470)(in class) List all significant differences between the crania of the robust australopithecine to that of H. habilis and H. rudolfensis .(in class) Compare the crania of H. habilis and H. rudolfensis. What differences are apparent? What similarities are apparent? (at home) Based on morphological and temporal comparisons, can P. boisei, or any ofthe robusts be ancestral to genus Homo?(at home) P. boisei males were roughly twice as large as females, while H. rudolfensis males were only about 25% larger than females. How might social behavior differ between these species? Why might it be different? Are there any modern primates with which you could draw analogies? Station 5 - Early Homo versus modern Homo sapiens (in class) Compare the crania of these species and record the relative differences revealedin your observations on the table below:Homo rudolfensis African Homoerectus (H.ergaster)Homo sapiensSupraorbital TorusDegree of PrognathismCranial CapacityMorphology of Face (Size and Shape)Overall Shape of Cranial VaultThe Hominid Family Tree up to H. erectus - Based on your comparisons above and in previous labs, sketch out a rough “family tree” that includes all the australopithcines you know, as well as, early Homo and H. erectus. Since there is no universal answer, be sure to defend your sketch with insights and observations about derived traits, time scales, geographic location, etc. that you learned in lab or in the text. A well-defended answer will receive full credit even if there are a few errors. A time scale has been drawn to get you started. 1 mya2 mya3 mya4 myaReading Questions1. Based on modern analysis of the fossils, what conclusions have been reached about theanatomy and lifestyle of Gigantopithecus? How might humans have contributed to its eventual extinction? (#21)2. According to Leonard, what is the common thread for all the traits that are uniquely human? (#23)3. What conclusions about human speech did Cartmill and colleagues arrive at by lookingat the hypoglossal canal?