Question

Evolution A. Comparative Anatomy Skeletal components are the same in all vertebrate animals. 1. Observe the diagram of the forelimb bones (ulna, radius, carpals, metacarpals, and phalanges of the human, the bat, the bird, the frog, the cat and the lizard. 2. Compare the forelimb bones of each of the vertebrates with those of the ancestral bones. Which bones look similar to the bones of the ancestor? Which ones are different from the bones of the ancestor? 3. Note the function of the forelimbs of these organisms. a. How are the bones modified in the birds? Do these modifications correspond with the function? b. How about the bat's? c. How about the human's? B. Comparative Embryology Embryological development in all vertebrates is similar. 1. Notice the presence of the tail, pharyngeal pouches and vertebral column in all the vertebrates. 2. In fish and other aquatic animals, the pharyngeal pouches become gills. In humans, they develop into middle ear and the auditory tube, the tonsils, the thymus and parathyroid glands. 3. Compare the embryos. List the similarities you have observed.

Answer 1

A. Comparative Anatomy

1.

2.

Hanaon Human tave lengthed henes than anaster Hunerue ulna and adius ane chnilag, enewthaugh the length a Vumam ase lasge them aneshal bones hey cnauris appals and malacastals tluman hat iger bones(phakmges)i poiad middle omd distal phalann whoias un ancesteo ansits of diferent number phalowa oi bingens Prut: similas bnes- Wumuaus,laopale adius,mulatoapals Vžioalas bores-dna, phalges auduad n umbr bd thra is had targe bangh Bicd Simlas banes disinalor bonus-pals metalospels, and phalamges nudual un bat Phalanges tHemurus, tadius, ulma. (aopals aaapdls ond phalonges ae madiliel md are nol simlas to ahal of anastons lnb faey Sienlas, banes-Homeous, una sadias apal, meta cospals, phalngens CAll bones al fangs on simds in leck to tht dmostoo But Phdlanges numburs wried are

Cal Sumlor bones- tamuus oadiu, aalymelalal phalomgs Dissinmlae bares- alna alea is slighfhy leok esent to thd a ameska's linb 4 ulags and stoaigt that linb Liead She lang banes Radius lns, Hamau, Laopah, mlaopmala phalanges Pissimlbe bones All a the bans nar stmio o amastons The number phalangees 08 alss Srmilas thaugh the al hese bone ae slgetly Vasuied anleshoar

3.

The buaes: apals maletap and phalangs The elbod amd auhit jpint lo modhed onto plane, the nunbes ot Angie lphalang) Coopals ave husd he hp 4 the dislal pehon mb ase madified to allach feathars DThese modifautions ndwth te fonchon? Yes The madicahom es hight Sothe bones are heduted and are hollao b the belka alhchmenet ab leathos are hghly madhed Raducad and the taopals and mela Me madibied in bat ? Bats Poocbaimbs aoe tetoapod foe limbs The foaelimbs oe elongat ed, edud bone weight on lunibs 0 fhe fooelimbs are hedued to achiene a thage madihcahion (0esd wth he fenchon9 Yes Binabe to bidh, there mabiahon is legt lgat by wight

Humons thou ase bones madifed un humons9 Humans have opesile thumbs 1Thoy had dlongated adius dlna and Phatangers Humeaus i hely thikamd Do these modificah ms orospond with the tnchan? Yes. Humas use orelimbs fos laelong', graspung, pekig se. o they hane thickened humesus b hold dongeted phtlangers fer pnj and gnsi heauy de