Specimen of the Week 172
By Tannis M N Davidson, on 26 January 2015
It’s that time of year when the Christmas tree has been taken down, gifts have been put away, and all holiday food finally consumed. Folk head back to work, kids return to school and everyone gets on with the business of the new year.
However, for the young (and young-at-heart) January is prime time for the continued enjoyment of new toys and games. Instructions are now understood, multi-piece sets have finally been assembled and a new level of obsessive play-enthusiasm occurs. The post-Christmas clean-up is duly hampered by the constant setting-up and putting-away of various toy sets, 1000 piece puzzles and assorted crafty-painty-arty bits and bobs.
As a tribute to the toy-players and gamers out there, this week’s Specimen of the Week is…
** Dog Skull Array **
As the name suggests, these specimens may seem vaguely familiar to you. Known as man’s best friend, dogs have been kept as working, hunting and pet companions for at least 14,000 years and number between 700 million and 1 billion individuals (1).
What we have here is a group of seven domestic dog skulls. It is likely that this is a developmental series showing the cranial growth in an unknown (undocumented) breed of dog. The Grant Museum was donated this specimen in the 1980’s from Imperial College London following the closure of Imperial’s zoology department. Unfortunately, additional information regarding breed type or developmental age of the skulls was not passed along with this acquisition. What is evident is that the smallest (youngest) two skulls do not have teeth or fused cranial sutures – which suggests that these two were foetal or newborn animals.
Previously known as Canis familiaris, the domestic dog (Canis lupus familiaris) was reclassified in 1993 as a subspecies of the grey wolf (Canis lupus) following mitochondrial DNA analysis which showed that the domestic dog and grey wolf are extremely closely related, “differing from each other by at most 0.2% of mtDNA sequence” (2). However, current DNA evidence suggests that domestic dogs are not descended from grey wolves but were domesticated from a now-extinct wolf population, whereby the genetic closeness between these two subspecies is due to admixture (interbreeding) (3).
3. Happy happy, joy joy
I have to admit that I am quite charmed by these little pups. I find their ‘expressions’ rather delightful – full of an animated vivacity not often found in dead animal specimens. I can almost hear the chorus of barking. Admittedly, the wonky mounting and weak mandible articulation contribute to the lively appearance of the dogs – one which most of my colleagues find more disturbing than cute. A new survey among the GMZ staff has revealed that the dogs most often bring to mind: day of the dead, evil clown heads, shrunken heads, and traitor’s heads on spikes. However, some light-hearted/fun/game associations were also discovered such as Pez dipensers, cue balls on a pool table, dominoes and the classic arcade game – Whac-a-mole(dog).
4. A dead dog is for life…
…or at least we hope so. Securing the long term preservation of our collection is currently being undertaken in our Bone Idols project where 39 of the Grant Museum’s rarest and most significant skeletons are being deep cleaned, repaired, re-cased and remounted. While the pups didn’t quite meet the project criteria as being particularly rare or particularly significant (or in need of urgent work), they have undergone a recent conservation assessment and are in a stable condition needing only remedial treatment (mandible rewiring, new protective cover).
Tannis Davidson is Curatorial Assistant at the Grant Museum of Zoology
1. Gompper, Matthew E. (2013). “The dog–human–wildlife interface: assessing the scope of the problem”. In Gompper, Matthew E. Free-Ranging Dogs and Wildlife Conservation. Oxford University Press. pp. 9–54
2. Wayne, Robert K. (1993). “Molecular evolution of the dog family”. Trends in Genetics 9 (6): 218–224
3. Freedman, Adam H.; Gronau, Ilan; Schweizer, Rena M.; Ortega-Del Vecchyo, Diego; Han, Eunjung; Silva, Pedro M.; Galaverni, Marco; Fan, Zhenxin; Marx, Peter; Lorente-Galdos, Belen; Beale, Holly; Ramirez, Oscar; Hormozdiari, Farhad; Alkan, Can; Vilà, Carles; Squire, Kevin; Geffen, Eli; Kusak, Josip; Boyko, Adam R.; Parker, Heidi G.; Lee, Clarence; Tadigotla, Vasisht; Siepel, Adam; Bustamante, Carlos D.; Harkins, Timothy T.; Nelson, Stanley F.; Ostrander, Elaine A.; Marques-Bonet, Tomas; Wayne, Robert K.; Novembre, John (16 January 2014). “Genome Sequencing Highlights Genes Under Selection and the Dynamic Early History of Dogs”. PLOS Genetics (PLOS Org) 10 (1): e1004016. doi:10.1371/journal.pgen.1004016 (accessed 22 January 2015)