[ad_1]
Scientists have successfully sequenced DNA from a 120-135 million-year-old weevil found in Lebanese amber, but reviving larger and older animals remains difficult due to the challenge of finding intact DNA. Soft tissue from Pleistocene species is available, making the revival of Neanderthals and other species feasible. The technology raises ethical questions, but human curiosity is likely to drive its development.
The short answer: for insects it’s very likely, for larger and older animals it might be difficult. Scientists have successfully isolated DNA from a 120-135 million-year-old weevil found in Lebanese amber, amplified it using polymerase chain reaction (PCR), and sequenced it. Not his entire genetic code, but portions of it. This genetic information was compared to modern weevils for phylogenetic analysis. This isn’t the revival of extinct species, but it’s a very important step in that direction.
There are a number of technical challenges in trying to revive extinct species, but none seem impossible to overcome. The hardest step is finding enough intact DNA. Since amber is organic and seals trapped insects in an airtight enclosure, the degradation of the genetic material is quite slow. In typical fossils, little or no organic material remains, because the fossil is not the organic material itself, but inorganic silts that replace the organic material as it decomposes. Until 2005, fossilization was thought to always replace the original material, but discoveries about the soft tissue of Tyrannosaurus Rex, including the identification of the original collagen proteins, have upset this common wisdom.
Reviving extinct species would require finding large portions of the original genetic material. Soft tissue is available for Pleistocene species, such as mammoths, cave bears, dire wolves, and even Neanderthals, and some scientists have even made sequencing efforts. This often requires multiple samples, as no single sample is likely to contain the entire uncontaminated DNA sequence. In Jurassic Park, gaps in dinosaur DNA have been replaced with segments of frog DNA, but this is problematic because it is assumed that scientists knew which dinosaur genes matched which frog genes were joining. As genetics advances, it will become easier to create these hypotheses, although it is likely that substantial portions of the original genetic material are still needed.
There is consensus among scientists that the revival of Pleistocene species, especially Neanderthals, is completely feasible and only a matter of time. If the entire genome can be sequenced, it can be synthesized and injected into a fertilized egg cell on a related species (such as birds), then grown in an artificial egg or uterus. It was previously seen as a challenge to create a suitable artificial egg, but more recently scientists are developing an environment that should work to raise almost any embryo.
Before we see ancient species like dinosaurs revived, we’re likely to see species from the Pleistocene. The possibility of reviving extinct species raises many ethical questions, but human curiosity is so great that it seems unlikely that the technology will be withheld for long if it is technologically feasible.
[ad_2]