Using OsteoID

Lots of materials can be mistaken for bone, including rocks, sticks, coral, etc. Bones have an outer dense layer (called the cortical bone), which if broken away reveals lots of tiny struts in the inside (called trabecular, cancellous, or spongy bone). Exposed trabeculae is a good sign you have a bone. The long bones (making up most of the limbs), will also have a hollow center called the medullary cavity. It’s not uncommon for people to find discarded animal remains with signs of butchery, such as the saw cuts to two of the examples shown.

Bones undergo some changes during growth and development which could affect the identification process. For example, long bones start off just as the shaft (diaphysis). Their ends (epiphyses) which will form the joints begin to develop separate from the shaft. This allows the shaft of the bone to grow (and the animal get larger). When the animal is done growing those ends (epiphyses) will fuse on to the shaft and growth will cease. All of the measurements in OsteoID are based on skeletally mature specimens. (If we included juveniles there would be too much size overlap, given how much size changes during growth and development).

How do I know if what I have is an adult?

See the picture below for an example of a juvenile pig femur. The ends of the bone (epiphyses) are not fused on (but put in place in the top left image).

If the epiphyses are not fused on at all the ends of the shaft will have this wavy appearance – its texture is also more porous. This means you’re missing the epiphyses. The measurements will not work in OsteoID, AND it’ll be difficult to visually compare, given that you’re missing some of the most diagnostic features. Still, you may try to compare to the photos.

If the epiphyses are fully fused on (as in an adult), instead you’ll have the smooth joint surface where it articulates with another bone. You can use both the size and visual comparison components of OsteoID.

If the epiphyses are fused on, but there is still a line of fusion (i.e., the ends aren’t fully integrated into the shaft), then your specimen isn’t quite an adult, but would be nearing adult size. You can try using the measurements, but they may not be as accurate. But with tends in place, you should still be able to do a visual comparison. Choose the element you have and scroll through the images.

Choose what “element type” you have (if possible). From OsteoID homepage scroll through the pictures and find what element or bone type best matches your specimen. Although there are species differences, the same element generally has similarity across species (especially within a Class such as mammals). The button for each element provides examples of three mammal bones, a turtle bone, and a bird bone for each element to help in the decision-making process. If you can’t figure out what bone you have, you can “Search All Bones.”

Once you find your element type (or decide to “search all”) click on that button and it will take you to a new page. The bone type you chose should be checked in the left column indicating that your search is being filtered to just that element. If you “searched all” no bones will be checked (as no filtering is applied). You can add or change the element using the filtering buttons under “Bone Type” in that column.

*Note: for tibia with a fused fibula, search under tibia.

*If you have a radius or radio-ulna and are not having luck, try searching the other one (e.g., if there’s not a picture under radio-ulna, search radius, and vice-versa). Some species are variably fused, a radio-ulna may have been broken apart, or dried ligaments may be holding the elements together when they are not actually fused.

*For the metapodials. Look at the cross-section shape of the bone. If it is “C” or “D”-shaped it will be a metacarpal, if it is more rounded or hexagonal it will be a metatarsal.

What if my element looks nothing like those?

OsteoID focused primarily on the long bones given that their measurements were comparable, along with a few other elements (sacrum, os coxae, and scapula). It is possible that your bone represents a different element, such as a vertebra or rib. We did not collect measurements on those other elements. We did, however, try to take as many photos as possible. Photos of other non-measured skeletal elements are accessible via a dropbox link. It is also possible that you have a species not included in OsteoID. See the “Additional Resources” tab for the dropbox link, as well as a list of other potential resources that may be of use. More guidance is also given under the FAQ tab.

What if I think I know what animal it is to start with?

Just choose “Search All Bones” to start with and when at the data page you can search either by the common name or the scientific name. Only fill out one box though, either common name, genus or species.

While you can just search through all of the images, OsteoID also allows you to narrow your results by filtering based on the specimen size. You can only filter by one measurement at a time, but the results are “nested”. E.g., if you put in a length and hit “GO”, it will limit the results to those species in which your length falls. You can then put in a proximal width and hit “GO” and it will further limit the results (i.e., it is now using both the length and width). It essentially just added another filter. **Thus, when doing a new search or changing the search to a new bone you have to hit “RESET” to clear the current filters!**

**Measurements are in millimeters (mm). If you measured in inches multiply by 25.4 to get the millimeter measurement.**

If you have the whole bone, it is recommended that you first try to filter by the bone Maximum Length. This is the easiest measurement to take. It is a true maximum from the most projecting point at the top (proximal end) to the most projecting point at the bottom (distal end). If you would like you can then enter the maximum proximal width (maximum width at the top of the bone) or the maximum distal width (maximum width at the bottom of the bone) to further narrow your results.

If you don’t have the whole bone, if you just have either the top (proximal) or bottom (distal) portion you can still enter the widths into OsteoID to narrow your results based on size.  The widths are medio-lateral measurements (i.e., breadths) taken with the front (anterior) surface of the bone facing you.

There’s no photo?

While we tried to get photos of everything, OsteoID is missing a few photographs of elements. You will still see the measurement ranges. See the “Additional Resources” page for other places to look for photos or try searching the internet for images based on what species came back in that range.

I can’t tell if it matches…

Some species do have subtle differences between them. As part of this project we did 3D scan a number of elements. See the “Additional Resources” page for a link to the 3D files. Perhaps viewing the element in three-dimensions will help. Remember, color doesn’t matter for species. Occasionally some of the specimens have drill holes (for grease) which should be ignored. There is also individual variation. Try to gauge how much your specimen really varies from the example and compare that to the other elements.

Note! OsteoID is meant to be a tool – it is meant to assist in identification. Visual comparison is key in making final species identifications and at times it may be appropriate to have an expert involved.

I’m having trouble….

See the FAQ tab for some trouble-shooting suggestions.

I think I have a human bone....

CONTACT YOUR LOCAL LAW ENFORCEMENT AGENCY and disturb as little as possible if it is still at the scene. They will know what to do from there.

Remember to hit “RESET” in between searches or when changing parameters.