Biological Data Analysis: Homework 10

Due Thursday, Nov. 19



You must type this and all other homework assignments. Do not e-mail the assignment to me; turn it in early (at 322 Wolf) for a foreseeable absence, or turn it in late after an unexpected absence from class.

1. McDonald (1989) collected the amphipod crustacean Platorchestia platensis on a beach near Stony Brook, Long Island, in April, 1987, counted the number of eggs each female was carrying, freeze-dried them, weighed them, then used protein electrophoresis to determine the genotype at the locus for mannose-6-phosphate isomerase (Mpi). The data consist of the identification number of the individual, the weight (in mg), the number of eggs, then the genotype. The biological question is whether the Mpi genotypes differ in size-adjusted fecundity. Analyze with ancova, using SAS. You must show your SAS program and the SAS output.

Amphipod crustacean, Platorchestia platensis. Photo from Tokyo Bay Ecosystem Research Center.

1301      5.42      29      fs
1302      5.38      29      ss
1303      7.36      23      ss
1304      4.47      19      fs
1305      5.75      23      ff
1306      7.27      25      fs
1307      6.64      13      fs
1308      4.67      22      ff
1309      5.55      24      ff
1310      6.13      22      ss
1311      8.94      25      fs
1312      5.85      22      ff
1313      4.15      16      ff
1314      9.91      27      fs
1315      8.57      23      fs
1316      4.75      20      ss
1317      6.89      17      fs
1318      6.64      21      fs
1319      7.12      20      fs
1320      5.92      19      ff
1321      7.06      27      ff
1322      7.48      33      fs
1323      6.14      23      fs
1324      5.85      26      fs
1325      6.69      21      fs
1326      8.10      25      ss
1327      4.97      25      ff
1328      4.15      23      fs
1329      8.62      25      ss
1330      6.30      17      ss
1331      6.68      26      fs
1332      4.46      22      ff
1333      7.44      24      ss
1334      5.38      28      ff
1335      4.64      15      fs
1336      7.93      21      fs
1337      4.18      20      ff
1338      5.69      21      ff
1339      7.04      25      fs
1340      6.41      16      fs
1341      3.70      18      fs
1342      7.26      20      ss
1343      7.17      27      ss
1344      4.78      27      fs
1345      8.24      26      fs
1346      4.68      24      fs
1347      5.25      16      ff
1348      4.64      24      ff
1349      7.78      24      ss
1350      6.23      21      ss
1351      3.96      21      fs
1352      5.42      22      ss
1353      4.86      13      ff
1354      7.87      22      ss
1355      4.56      20      ff
1356      6.36      19      fs
1357      5.25      23      ss
1358      4.38      22      fs
1359      4.58      22      fs
1360      5.74      18      fs
1361      7.37      35      ss
1362      6.14      23      fs
1363      7.25      22      fs
1364      5.21      22      ff
1365      8.56      28      fs
1366      8.01      27      ss
1367      7.38      16      fs
1368      6.71      21      fs
1369      6.85      20      fs
1370      4.92      23      ss
1371     10.16      35      fs
1372      7.02      29      fs
1373      5.71      16      ff
1374      7.03      25      ss
1375      6.45      24      ss
1376      6.52      26      ff
1377      5.50      29      fs
1378      5.53      23      ff
1379      4.91      23      ff
1380      6.81      31      fs
1381      5.51      27      fs
1382      9.58      30      fs
1383      5.06      19      ss
1384      7.77      22      fs
1385      7.11      19      fs
1386      6.72      21      ss
1387      7.24      27      fs
1388      5.51      24      ff
1389      7.47      30      ff
1390      6.72      32      fs
1391      7.05      22      fs
1392      6.92      19      fs
1393      6.07      18      fs
1394      6.63      24      fs
1395      7.00      20      ss
1396      4.85      20      ff
1397      3.97      16      fs
1398      3.95      17      ff
1399      5.49      26      ff
1400      8.49      19      fs
1401      4.54      26      fs
1402      6.51      27      ff
1403      5.71      13      fs
1404      3.44      13      fs
1405      9.39      33      ss
1406      7.42      17      ff
1407      6.49      17      ss
1408      5.66      15      fs
1409      4.75      22      fs
1410      4.82      27      fs
1411      8.20      31      ff
1412      7.27      32      fs
1413      7.09      19      fs
1414      6.34      21      ss
1415      6.16      25      ss
1416      5.74      22      ss
1417      7.63      22      ff
1418      5.89      25      fs
1419      6.86      23      fs
1420      4.22      17      fs

2. Arnbom et al. (1994) weighed female southern elephant seals, Mirounga leonina, and recorded the sex of their offspring. The table below shows the weight (rounded to the nearest 20 kg), the number of male pups of mothers in that weight class, and the number of female pups of mothers in that weight class. Perform a logistic regression using SAS, interpret the results, and graph the proportion of males vs. mother's weight. You must print your SAS program and the SAS output.


weight  males  females
300       0       3
340       0       1
360       0       1
380       1       8
400       4       2
420       5       7
440       5       5
460       7       5
480       5       7
500       5       8
520       3       4
540       4       4
560       2       3
580       4       4
600       3       2
620       6       5
640       2       4
660       3       2
680       1       0
700       3       1
720       2       0
740       2       0
760       0       1
780       2       0
800       0       1
820       1       2
980       1       0

References

Arnbom, T., M.A. Fedak, and P. Rothery. Offspring sex ratio in relation to female size in southern elephant seals, Mirounga leonina. Behav. Ecol. Sociobiol. 35: 373-378.

McDonald, J.H. 1989. Selection component analysis of the Mpi locus in the amphipod Platorchestia platensis. Heredity 62: 243-249.



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This page was last revised November 15, 2013. Its URL is http://udel.edu/~mcdonald/stathw9.html