TABLE 1.

Number of retrieved clones, stratigraphic age, core number, and drilling depth (meters below the surface) for the four sedimentary samples

Sample layer	Age (103 yr)	Core no.a	Depth (m)	No. of clones
				125 bp	210 bp	510 bp	Total
Modern	0	1	0.5	25	9	33	67
Holocene	10	1	4.0	—b	21	22	43
Late Pleistocene	20	2	4.8	34	19/25c	30	108
Pleistocene	300-400	4	9.2	25/18c	35	36/22c	136

^aSee reference 27 for core numbers.

^bAmplification of 125 bp from the 10 ky sample failed. Spiking of samples with Humicula insolens genomic DNA, prior to cycling, revealed inhibition of the PCR in the 10 ky sample (results not shown).

^cThe number after the shill is the number of clones independently obtained in Oxford.