Plate Tectnics and the Fssil Recrd Accrding t the thery f plate tectnics, the earth's surface is dynamic. The current cnfiguratin f its land and cean masses is the result f mtins that have ccurred ver the curse f billins f years. The earth's surface sits atp a series f lithspheric plates that are in cnstant, slw-speed mtin. Snapshts f its surface, at di!erent pints in its histry, wuld reveal a planet unlike that which we picture tday. If, in fact, the earth's landmasses have nt been statinary, there shuld be evidence t supprt this thery. Yu will explre the fssil recrd t see if it prvides any substantiatin fr the claims f plate tectnics. The fllwing data describes the distributin f fssils fr fur di!erent genera. Use the prvided gegraphic infrmatin t plt the lcatin f each fssil find n the Wrld Map Handut. Use a di!erent clr t represent the area in which each genus has been discvered; prvide a clr key. 1. The genus Glsspteris represents a grup f seed-bearing ferns, cmprised f ver 200 di!erent species. Fssils fr these ferns have been fund in Pennsylvanian and Permian rck layers, thus dating them t the Palezic era, which ccurred apprximately 260 millin years ag. Descriptin f Fssil Lcatin: Glsspteris Suth America: fssils have been fund in a small area that extends frm the middle f the cntinent t its eastern cast. Africa: fssils have been fund in a band that extends frm the west t the east cast. Madagascar: fssils have been fund n the bttm half f the island. India: fssils have been fund n the bttm half f the cuntry. Australia: fssils have been fund in a band that extends frm its sutheastern cast almst all the way t its nrtheastern cast. Latitude and Lngitude (apprximate) a band frm 32 S, 65 W t 34 S, 53 W that extends back t 37 S, 58 W 25-29 S n the west cast t 11-15 S n the east cast the suthern prtin f the island, up t 20 S n the west cast and 18 S n the east cast India's suthern prtin, up t 14 N n its west cast and 10 N n its east cast frm 125-130 E, alng its suthern cast, in a band that extends up t 20 S, 133 E
Antarctica: fssils have been fund in an L-shaped band that extends frm its nrtheastern cast t the east. frm 80-90 E, alng its nrthern cast, turning t the east between 82-90 S
2. The genus Cyngnathus is cmprised f terrestrial, meat-eating reptiles frm the Triassic perid (200 millin years ag). Descriptin f Fssil Lcatin: Cyngnathus Suth America: fssils have been fund in a wide band that extends, acrss its midsectin, cast t cast. Africa: fssils have been fund in a band that extends frm the west t the cntinent's midsectin. Latitude and Lngitude (apprximate) 15 S, 75 W t 22 S, 71 W n the west cast; 17 S, 40 W t 24 S, 49 W n the east cast 5 S, 11 E t 11 S, 13 E n the west cast; 5 N, 25 E t 4 S, 25 E at its midsectin 3. The genus Messaurus cntains fresh water reptiles whse fssils have been discvered in Permian rck layers thught t be abut 225 millin years ld. Descriptin f Fssil Lcatin: Messaurus Suth America: fssils have been fund in a wide band that extends, acrss its suthern prtin, cast t cast. Africa: fssils have been fund n a small sectin f the cntinent's suthern tip. Latitude and Lngitude (apprximate) 35-22 S alng the west cast t 38 S - 45 S n the east cast frm 30-35 S n the west cast, extending t 29 S, 28 E at the pint furthest east 4. The genus Lystrsaurus, like Cyngnathus, cnsists f land-dwelling reptiles which lived during the Triassic perid, 200 millin years ag. Descriptin f Fssil Lcatin: Lystrsaurus Africa: fssils have been fund in a band that extends frm the east cast back t its suthern midsectin. Madagascar: fssils have been fund n the tp half f the island. India: fssils have been fund in the tp third f the cuntry. Latitude and Lngitude (apprximate) 3 S, 41 E t 12 S, 40 E n the east cast, extending west back t 15 S, 17 W the entire nrthern tip f the island, frm 18 S n the west cast t 16 S n the east cast India's nrthern prtin, frm 16-20 N n its west cast t 20-23 N n its east cast; the
nrthernmst pint in the band is 25 N, 76 E Antarctica: fssils have been fund in a small band that extends frm its nrtheastern cast dwn t the Glsspteris band. frm 103-110 E, alng its nrthern cast, dwn t the Glsspteris band at 82 S
Analysis After examining the fssil infrmatin prvided in the charts abve, as well as the fssil distributin plt yu created, answer the fllwing questins, n yur wn paper. 1. Assuming that the lcatin f the cntinents has nt changed in the last 250 millin years, are there reasnable explanatins that yu can prvide fr the bserved distributin patterns f each f the genera? What culd accunt fr the fssil recrd? 2. Based upn the distributin patterns yu nted, is there evidence t suggest that the cntinents have, in fact, mved ver the earth's histry? What arrangement f cntinents des yur data imply? Are there reasns why the bserved distributin patterns culd nt have develped in the absence f cntinental mvement? 3. Cut ut each f the cntinents frm yur map, and rearrange them in a pattern that is cnsistent with the fssil evidence. Glue r tape the landmasses n yur answer sheet, alng with the clr key. Explain the reasning behind the arrangement yu've created. Nte: the wrld map des nt represent Antarctica very accurately, s it may nt fit in yur arrangement as neatly as the ther landmasses. 4. What ther types f evidence, in additin t the fssil recrd, wuld supprt the thery f plate tectnics? SAS Curriculum Pathways Cpyright 2015 SAS Institute Inc., Cary, NC, USA, All Rights Reserved