R EPORTS phase environments (20) and, we may as- 4-mm silicon nitride rotors with Torlon caps. Tagish 27. I. Gilmour, V. K. Pearson, M. A. Sephton, Lunar Planet. sume, were also abundant in the solar nebula. Lake repeat analyses were at 0.5-, 1.0-, and 2.0-ms Sci. 32 (abstract 1993) (2001). contact time. 28. J. Han, B. R. Simoneit, A. L. Burlingame, M. Calvin, The alternative possibility exists that aliphat- 17. G. D. Cody, C. M. O’D Alexander, F. Tera, Lunar Planet. Nature 222, 364 (1969). ic hydrocarbons in the meteorite underwent Sci. 30 (abstract 1582) (1999) [CD-ROM]. 29. J. R. Cronin, S. Pizzarello, D. P. Cruikshank, in Mete- condensation and aromatization as in terres- 18. A. Gardinier et al., Earth Planet. Sci. Lett. 184,9 orites and the Early Solar System, J. F. Kerridge, M. S. trial kerogens. However, such thermal alter- (2000). Matthews, Eds. (Univ. of Arizona Press, Tucson, AZ, 19. ␦D values were determined by thermal conversion 1988), pp. 819Ð8857. ation would not be consistent with the hydro- (TC)/elemental analyzer (EA) interfaced to Finnigan 30. G. W. Cooper, J. R. Cronin, Geochim. Cosmochim. gen abundance of the material, which implies DeltaϩXL MS. Pyrolysis was at 1450¡C to yield hy- Acta 59, 1003 (1995). drogen gas quantitatively. Standardization was by ␦ ϭ Ϫ ϫ 3 an incomplete condensation of rings, the 31. ‰ (Rsample Rstandard/Rstandard) 10 . For car- ϭ 13 12 finding in the extracts of labile molecules, as hydrogen gas pulse; sample analyses were repeated bon, R C/ C and the standard is VPDB. 10 times. ␦13C(VPDB) of isopropanol: Ϫ29.3‰ (EA-IRMS). ␦13C nitriles, and the presence of a substantial ␦13 ϭ ␦13 Ϫ 20. L. J. Allamandola, S. A. Sanford, B. Wopenka, Science mass balance equations: Cdiacid [ Cder. diacid aliphatic phase in more petrologically pro- 237, 56 (1987). a(Ϫ29.3)]/b (a and b are fractional carbon abundances cessed chondrites, as CVs (7). 21. J. F. Kerridge, S. Chang, R. Shipp, Geochim. Cosmo- of isopropanol and diacid, respectively). A proce- chim. Acta 51, 2527 (1987). dural succinic acid standard gave no substantial Far from disappointing, the relative simplic- 22. 1.3 ppm of fullerenes was isolated from the bulk carbon fractionation. ity of Tagish Lake organic content provides carbonaceous residues by extraction with 1,2,3,5 tet- 32. We thank M. Zolensky, A. Hildebrand, and J. Brook for insight into an outcome of early solar system ramethylbenzene. The yield was incomplete, as for providing the Tagish Lake sample; J. Cronin for much chemical evolution not seen so far. In particu- other meteorites (23), because of limited organic help and suggestions; C. Moore for supporting a solubility of fullerenes. student assistant; and four anonymous referees for lar, the finding of just one suite of organic 23. L. Becker, R. J. Poreda, T. E. Bunch, Proc. Natl. Acad. helpful reviews. We gratefully acknowledge conver- compounds matching those of Murchison and Sci. U.S.A. 97, 2979 (2000). sations with M. Bernstein, C. Chyba, J. Dworkin, I. of some (but not all) the carbonaceous phases 24. Helium within the extract was ϳ0.01% of total Gilmour, D. Hudgins, W. Huebner, and A. Primak. The helium in the bulk material. About 40% of this total work was supported by NASA grants from the Exo- and compounds seen in other chondrites dem- helium is released below 800¡C, consistent with the biology (S.P., Y.H., and G.C.) and Cosmochemistry onstrates the presence of distinct organic syn- extracted fullerene carrier. No other carbon carrier (L.B.) Divisions and NSF grant CHE9808678 (NMR). thetic processes in primitive meteorites. It also has been identified with similar low-temperature re- implies that the more complex organic matter lease pattern. 17 May 2001; accepted 14 August 2001 25. E. T. Peltzer, J. L. Bada, Nature 272, 443 (1978). Published online 23 August 2001; of heterogeneous chondrites may result from 26. I. Gilmour, M. A. Sephton, V. K. Pearson, Lunar Planet. 10.1126/science.1062614 multiple, separate evolutionary pathways. Sci. 32 (abstract 1969) (2001). Include this information when citing this paper. References and Notes 1. J. R. Cronin, S. Chang, in The Chemistry of Life’s Origins, J. M. Greenberg, C. X. Mendoza-Gomez, V. Origin of Whales from Early Pirronello, Eds. (Kluwer Academic, Dordrecht, Neth- erlands, 1993), pp. 209Ð258, and references therein. 2. C. F. Chyba, C. Sagan, Nature 355, 125 (1992). Artiodactyls: Hands and Feet of 3. P. G. Brown et al., Science 290, 320 (2000). 4. S. Pizzarello, G. W. Cooper, Meteoritic Planet. Sci. 36, 897 (2001). Eocene Protocetidae from 5. J. R. Cronin, S. Pizzarello, S. Epstein, R. V. Krishnamur- thy, Geochim. Cosmochim. Acta 57, 4745 (1993). 6. J. R. Cronin, S. Pizzarello, Geochim. Cosmochim. Acta Pakistan 54࿜࿜࿜࿜, 2859 (1990). 7. , J. S. Frye, Geochim. Cosmochim. Acta 51, Philip D. Gingerich,1* Munir ul Haq,1,2 Iyad S. Zalmout,1 299 (1987). 2,3 2 8. The compounds were analyzed by GC-MS as isopro- Intizar Hussain Khan, M. Sadiq Malkani pyl esters. The GC columns were ChyrasilDEX (Chrompack; 25 m by 0.25 mm) or Chirasil-Val (All- tech; 50 m by 0.25 mm). The typical program was Partial skeletons of two new fossil whales, Artiocetus clavis and Rodhocetus Ϫ Ϫ 40¡C initial, 5 min; 100 at 2¡/min; and 200 at balochistanensis, are among the oldest known protocetid archaeocetes. These 4¡/min. 9. GC-C-IRMS: HP 6890 GC, Finnigan high-temperature came from early Lutetian age (47 million years ago) strata in eastern Balo- conversion interphase III, and Mat Deltaϩ-XL MS. GC chistan Province, Pakistan. Both have an astragalus and cuboid in the ankle with conditions were as for GC-MS (8). Oxidation was at characteristics diagnostic of artiodactyls; R. balochistanensis has virtually com- 940¡C with a ceramic oxidation reactor bearing NiO/ ␦13 plete fore- and hind limbs. The new skeletons are important in augmenting the CuO/Pt wires. Standard CO2 (six pulses) C: Ϫ10.07‰ (VPDB). Data were analyzed with Finnigan diversity of early Protocetidae, clarifying that Cetacea evolved from early ISODAT software, with ␴ϽϮ0.3‰ for peaks Ͼ0.5 V. Artiodactyla rather than Mesonychia and showing how early protocetids swam. 10. Ϫ85‰ to Ϫ5‰, up to ϩ5‰ for methanogenic bacteria. 11. These acids were analyzed with DB-17 column (60 m Whales are marine mammals grouped in the amenable to study in the fossil record. Living by 0.25 mm; Agilent Technologies). Other ␦13C val- order Cetacea (1). Most mammals live on land whales are so distinctive, and intermediate fos- ues were ϩ7.7 Ϯ 0.3‰ for a methyl-phthalimide and the fossil record of early mammals is ter- sils sufficiently rare, that a half-century ago and ϩ5.9 Ϯ 0.7‰, ϩ10.5 Ϯ 0.8‰, and ϩ17.5 Ϯ 0.4‰ for three dimethyl-phthalimides. restrial. Thus, it has long been reasonable to Simpson regarded Cetacea as “on the whole the 12. J. G. Lawless, G. U. Yuen, Nature 282, 396 (1979). infer that the origin of whales involved an evo- most peculiar and aberrant of mammals,” insert- 13. G. W. Cooper, M. H. Thiemens, T. Jackson, S. Chang, lutionary transition from land to sea. This is one ing them arbitrarily in his classic 1945 classifi- Science 277, 1072 (1997), and references therein. of the most profound changes of adaptive zone cation of mammals (2). In response, Boyden and 14. M. H. Studier, R. Hayatsu, E. Anders, Geochim. Cos- mochim. Acta 36, 189 (1972). Gemeroy (3) applied innovative immunological 15. Airborne contamination can be absorbed readily by 1Department of Geological Sciences and Museum of precipitin tests and found much higher cross- meteorites (28) and should be considered for Tagish Paleontology, The University of Michigan, Ann Arbor, reactivity of Cetacea to Artiodactyla than to Lake, which was recovered a week after its fall. 2 MI 48109Ð1079, USA. Geological Survey of Pakistan, other living orders of mammals. Van Valen (4) 16. Operating conditions were as follows: Varian Sariab Road, Quetta, Pakistan. 3Department of Earth INOVA400 spectrometer at 9.4 T with the VACP MAS Sciences, University of New Hampshire, Durham, NH attempted to reconcile close relationship of sequence, 50-kHz spectral width, 3.5-ms cross-polar- 03824Ð3589, USA. whales and artiodactyls with the then-known ization contact time, recycle delay of 1.04 s, 6.7-␮s 1H90 pulse width, 28,584 transients per spectrum, *To whom correspondence should be addressed. E- fossil record by proposing that whales originat- 55-kHz decoupling field, 16.0-kHz spinning rate, and mail: [email protected] ed from Paleocene mesonychid condylarths, www.sciencemag.org SCIENCE VOL 293 21 SEPTEMBER 2001 2239 R EPORTS whereas artiodactyls originated from closely ing fore- and hind limbs. Protocetidae are gen- ically (circa 0.5 million years) than other early related Paleocene arctocyonid condylarths. erally considered to be ancestral to later Basi- protocetids (8, 34), and its proportions are like- Most morphologists and paleontologists have losauridae and, hence, on the main line of ceta- ly to be primitive for the family. favored a mesonychid origin of whales (5– cean evolution (1). One of the new skeletons The skeleton of Artiocetus was located 14), but further immunological, DNA hybrid- represents a new genus and species, and the after pieces of ankle bones, including a com- ization, and molecular sequencing studies second represents a new species within an ex- plete left astragalus, partial left calcaneum, support close relationship of Cetacea to artio- isting genus. Both come from transitional beds and complete left cuboid, were found on the dactyls (15–18) and more specifically to hip- at the top of the Habib Rahi Formation and base surface.