By Oliver Haddrath, Ornithology Technician
DNA testing over the last 30 years has revolutionized many different fields ranging from health care to law enforcement to the study of human civilization and natural history. The ROM was quick to adopt techniques such as DNA sequencing and genetic fingerprinting as powerful tools to help study its collections.
In its simplest application, looking at DNA allows the identification of organic material with great precision. For example, back in the 1980’s a whale vertebra was found while digging an extension to the Toronto subway system. Looking at the bone’s size and shape it could be narrowed down to having come from a toothed whale. What kind of whale and how it got there was still a mystery and it generated considerable interest and even a documentary on the subject made by Peter Lynch called “A Whale of a Tale”. DNA extracted from a tiny fragment of the whale bone in the ROM’s DNA lab positively identified it as coming from a killer whale, and with further work it would even be possible to tell if it was a male or female and where in the world it likely came from. How it came to be buried 22 metres below ground at the Toronto waterfront still remains a mystery, however much of that area is landfill.
Aside from identifying the occasional unusual find, work in the DNA lab is mostly focused on two tasks: the building of the tree of life and the conservation of rare and endangered species. The first task involves building on the century old process which used comparative methods based on anatomy and morphology to determine how all living organisms on the planet are related to each other. As DNA is the material passed down from generation to generation sequencing it can provide large amounts of information and in some cases overturn what was thought before. As DNA mutates with time, past mutations can function like the ticking of a clock to allow us to date when species diverged, making it possible to examine what influences events such as ice ages and continental breakups may have had on how species diversified. For the second task of conservation, DNA from individuals can provide critical information on population dynamics and levels of genetic diversity which can help in making informed decisions on captive breeding programs and assigning conservation priorities.
The last five years have seen an explosion of new DNA sequencing technologies. Whole genomes (the complete sequence information stored in the DNA of an individual) are now routinely being sequenced from both living and extinct species. Genomic research performed in institutions around the world have revealed surprising results and shown that our own family tree is far more complicated than anyone ever imagined. For example, comparisons between genomes have shown that most of the people on this planet have 1-4% of their genome originating from Neanderthals.
The ROM has recently also embarked on several genome sequencing projects in partnership with other institutions, not on humans but on birds, with the aim to gain new insights on how birds and some of their unique traits have evolved.
All these new technologies hold the promise to keep improving our understanding of how life arose, evolved and diversified into the millions of different species we see around us today.