Last updated on: July 16, 2025

Best Ways to Preserve Animal Skeleton Specimens

Preserving animal skeleton specimens is a crucial practice in various fields such as biology, paleontology, education, and museum curation. Proper preservation allows researchers, educators, and enthusiasts to study anatomy, taxonomy, and evolutionary biology in greater detail. However, preserving skeletal specimens is an intricate process requiring care, precision, and appropriate methods to ensure the bones remain intact, clean, and free from damage over time.

This article explores the best ways to preserve animal skeleton specimens, covering preparation techniques, cleaning methods, degreasing processes, whitening treatments, and long-term storage tips to maintain their condition.

Understanding the Importance of Preservation

Animal skeletons provide critical insight into the structure and function of animals. Preserved specimens serve as educational tools in classrooms and museums and are invaluable for scientific research. Poor preservation can lead to degradation such as discoloration, brittleness, or microbial damage, which compromises the specimen’s value.

Proper preservation safeguards bones from decay caused by organic residues, oils, fats, microorganisms, or environmental factors like moisture and light.

Step 1: Preparing the Specimen

Before preservation begins, proper preparation is essential.

1.1 Obtaining Specimens Responsibly

Ensure that specimens are acquired ethically and legally. Many places have regulations regarding collection of wildlife remains.

1.2 Initial Cleaning

Remove Soft Tissue: Carefully remove flesh with scalpels and scissors. This can be time-consuming but is important for thorough cleaning.
Skinning: For larger animals, skinning helps expose bones.
Disarticulation: If necessary for study or display, separate bones carefully without causing damage.

Step 2: Cleaning Methods for Bones

Removing all organic material is vital because leftover tissue can cause odor and degrade the bone.

2.1 Manual Cleaning

Use tools such as brushes or picks to scrape off remaining tissue.
Avoid harsh scraping that could damage delicate bone surfaces.

2.2 Maceration (Water Decomposition)

Maceration uses warm water to loosen soft tissues through bacterial action.

Place specimen in a sealed container filled with water at around 30–40°C (86–104°F).
Change water every few days to prevent foul odor buildup.
Duration depends on size; small specimens may take days while large ones can take weeks.
This is natural but can produce unpleasant smells and requires ventilation.

2.3 Dermestid Beetles

Using dermestid beetles is an effective biological cleaning method.

Beetles consume flesh without damaging bone.
Ideal for delicate or complex specimens.
Requires a controlled environment to maintain beetle colonies.
Slow but yields excellent results with minimal damage.

2.4 Boiling or Simmering

Boiling can remove flesh quickly but must be done cautiously.

Boil bones gently instead of high heat to avoid bone cracking.
Too long boiling can make bones brittle or warp them.
After boiling, manually remove any remaining tissue with tools.

Step 3: Degreasing the Bones

Bones often contain fat and oils that can cause yellowing or become rancid over time if not removed properly.

3.1 Why Degrease?

Fat residues inside bones slow drying and encourage bacterial growth that damages the specimen.

3.2 Common Degreasing Agents

Ammonia Solution: Diluted ammonia bath (5–10%) helps dissolve fats.
Dish Soap: Soaking bones in warm soapy water over several days.
Acetone: Effective solvent but highly flammable; use with care in a ventilated area.
Enzymatic Cleaners: Commercial degreasers designed for preserving fossils or biological samples.

3.3 Procedure

Submerge bones fully in chosen degreaser.
Change solution frequently until no more grease leaches out.
Rinse thoroughly after treatment to remove chemical residues.

Step 4: Whitening and Disinfecting

Whitening enhances the visual appeal of specimens by removing stains and discoloration while disinfecting prevents microbial growth.

4.1 Hydrogen Peroxide Treatment

Hydrogen peroxide (H₂O₂) is preferred over bleach because it whitens without damaging bone integrity.

Soak bones in a solution of 3% to 12% hydrogen peroxide depending on size.
Exposure times vary from several hours to overnight.
Avoid prolonged exposure which may weaken bone structure.

4.2 Avoid Bleach (Sodium Hypochlorite)

Although bleach whitens effectively, it degrades bone collagen making bones brittle over time. Use it only as a last resort with extreme caution.

4.3 Drying after Whitening

After treatment:

Rinse thoroughly with water.
Allow bones to dry completely in a well-ventilated area away from direct sunlight.

Step 5: Assembly and Articulation (Optional)

For teaching displays or museum mounts:

Use wire, glue (such as cyanoacrylate), or epoxy resin to articulate bones.
Plan carefully to avoid stress points which could break over time.

Step 6: Long-Term Storage and Maintenance

Proper storage ensures longevity of your specimen:

6.1 Environmental Control

Store in cool, dry places away from direct sunlight to prevent UV damage.
Maintain stable humidity levels; excessive moisture encourages mold growth.

6.2 Protective Coatings

Applying a light sealant such as diluted PVA glue may protect bones but should be tested first on sample specimens to avoid unwanted discoloration or stickiness.

6.3 Pest Prevention

Keep specimens in sealed containers or display cases to prevent insect infestation which could damage them.

Additional Tips for Successful Preservation

Record all chemicals used during cleaning for future reference.
Label specimens with identification data before storage or display.
Handle specimens gently using gloves to avoid oil transfer from hands.
Always prioritize safety by working in well-ventilated areas and using protective gear when handling chemicals.

Conclusion

Preserving animal skeleton specimens involves a multi-step process requiring patience and attention to detail—from initial preparation and cleaning through degreasing, whitening, possible assembly, and finally proper storage. Each step plays an important role in maintaining the structural integrity and appearance of the bones over time.

By following best practices such as ethical sourcing of specimens, using gentle cleaning techniques like dermestid beetles or maceration, selecting safe whitening agents like hydrogen peroxide instead of bleach, and controlling environmental conditions during storage, you can ensure that your skeletal specimens remain valuable scientific and educational resources for years to come.

With these comprehensive guidelines on how to preserve animal skeletons effectively, enthusiasts and professionals alike can confidently prepare high-quality skeletal collections that withstand the test of time.