Analysing ancient DNA.

R J Cano

doi:10.1016/s0160-9327(96)10031-4

Home/Archive/PubMed

PubMed · 9022353

Analysing ancient DNA.

R J Cano

View original source ↗Export metadata ↓

Abstract

Much of what we know about extinct organisms comes from traits that are not preserved in the fossil record. Until recently, morphological analysis was the only tool available for scientists to determine relationships for extinct fossil organisms. We now know that "ancient' DNA can be preserved in the remains of extinct organisms. By targeting specific gene sequences, it may be possible to deduce biochemical characteristics and through sequence comparisons, to estimate the extent of evolutionary divergence. By comparing the amount and type of these changes, one could estimate how quickly some DNA 'evolves' relative to other segments, or which genes have the most flexibility or are more conserved over time. The compilation of these data would yield greater understanding of the physiology of extinct organisms and provide a much clearer picture of genetic change over time, and the mechanics behind 'evolution'.

Explore related subjects

Amber Base Sequence Conserved Sequence DNA Fossils Gene Amplification Phylogeny Polymerase Chain Reaction Software Journal Article Review

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

R J Cano. 1996. Analysing ancient DNA.. https://doi.org/10.1016/s0160-9327(96)10031-4

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Using electrospray-assisted pyrolysis ionization/mass spectrometry for the rapid characterization of trace polar components in crude oil, amber, humic substances, and rubber samples.

We describe the use of electrospray-assisted pyrolysis ionization/mass spectrometry (ESA-Py/MS) to selectively ionize trace polar compounds that coexist with large amounts of nonpolar hydrocarbons in crude oil, amber, humic substances, and rubber samples. Samples of different origins are distinguished rapidly by their positive ion ESA-Py mass spectra without prior separation or chemical pretreatment. During ESA-Py analysis, the samples in their solid or liquid states were pyrolyzed at 590, 630 or 940 degrees C using a commercial Curie-point pyrolysis probe. The gaseous pyrolysates were transferred into a glass reaction cell. The polar compounds (M) in the pyrolysates were then ionized by electrospray ionization (ESI), yielding protonated molecules (MH+). Although the major components of the pyrolysates are nonpolar hydrocarbons, their lack of functional groups that can receive a proton in the ESA-Py source results in no hydrocarbon ion signals being produced; thus, the positive ions detected in ESA-Py mass spectra all result from trace polar components in the pyrolysates.

Amber↗

PubMed2006

A microworld in Triassic amber.

Amber provides an effective medium for conservation of soft-bodied microorganisms, but finds older than 135 million years are very rare and have not so far contained any microbial inclusions. Here we describe 220-million-year-old droplets of amber containing bacteria, fungi, algae and protozoans that are assignable to extant genera. These inclusions provide insight into the evolution and palaeoecology of Lower Mesozoic microorganisms: it seems that the basal levels of food webs of terrestrial communities (biocoenoses) have undergone little or no morphological change from the Triassic to the Recent.

Amber↗

PubMed2006

A fossil bee from Early Cretaceous Burmese amber.

The bee fossil record is fragmentary, making it difficult to accurately estimate the antiquity of bee-mediated pollination. Here, we describe a bee fossil [Melittosphex burmensis (new species), Melittosphecidae (new family)] from Early Cretaceous Burmese amber (approximately 100 million years before the present). The fossil provides insights into the morphology of the earliest bees and provides a new minimum date for the antiquity of bees and bee-mediated pollination.

Amber↗