The Assembly of a New Human Osteological Collection: The XXI CEIC as a Forensic Pedagogical Tool

Abstract

This technical note aims to characterize and contextualize the creation of a new collection of identified skeletons stored in the University Institute of Health Sciences—CESPU. This project presents unique and innovative pedagogical opportunities, with students actively involved in the cleaning and processing of the bones and antemortem/postmortem information gathering, as well as in anthropology research projects. This XXI Century Identified Skeletal Collection is composed of 98 complete adult skeletons of both sexes and is still expanding, being the 10th contemporary collection available in Portugal. The skeletons consist exclusively of Portuguese nationals who died between 1946 and 2007, and the 42% that have been processed so far are in good preservation. Comparative learning outcomes after implementing this active learning strategy are not yet available. Improvements are expected since more participation and enthusiasm in classes and research were perceived.

1. Introduction

Ethically sourced human osteological collections of identified remains are rare. Yet, they allow for various types of scientific investigations and can be used by researchers worldwide, allowing specific population studies, such as the one performed by Cardoso et al. on the stature of Portuguese individuals [1], or by Peleg et al. on sex estimation, using an American collection [2]. Additionally, they can be of utmost importance in the pedagogical process, namely in teaching forensic anthropology and odontology, as they allow students to approach real scenarios found in forensic examinations [3]. Mann [4] has stated that skeletal collections also allow for studies on what he called the human skeletal triad, i.e., trauma, variation, and disease.

There are several osteological collections worldwide. Some come from skeletons used in dissections (as the ones in the Hamann-Todd Human Osteological Collection in Cleveland, USA) [5], others from autopsies (such as the set of foetuses in Hungary) [6]. Conversely, the Spitalfields collection in London was amassed because the crypts in which they were placed had to be emptied [5]. Lack of space is also the reason that led to the assembling of most Portuguese collections, as most come from municipal cemeteries that need more burial space, and remove unclaimed human remains from primary and secondary burial plots to provide space for new internments, cremate them or place them in collective ossuaries within the cemetery [5,7]. This occurs in several Portuguese cemeteries, but on different occasions, some municipalities have entrusted these remains to museums and universities for research and teaching purposes [7], being this the case of the present collection.

The first ones were amassed in Europe and the United States by surgeons, anthropologists, and physicians [8], being an established reference in physical anthropology, as they represent the prime basis for the development of basic techniques in forensic and biological anthropology such as biological profile estimation [9]. Currently, in Portugal, there are nine identified skeleton collections (

Table 1. Identified human skeletal collections in Portugal.

	Number of Individuals	Location	Death Dates
Ferraz de Macedo Collection [10]	40 (skulls only)	Lisboa	Before 1907
21st Century Identified Skeletal Collection [8]	302	Coimbra	1982–2012
CEIC XXI Collection	98	Porto	1946–2007
Coimbra Identified Skeletal Collection [11,12]	505	Coimbra	1904–1936
Évora Collection [13]	201	Évora	1870–1993
Identified collection of the National Museum of Natural History, Lisbon [14]	1692	Lisbon	1880–1975
International Exchanges Collection [12,15]	1142 (skulls only)	Coimbra	1904–1937
Medical School Collection [11,12]	632 (skulls only)	Coimbra	1895–1903
Mendes Correia Collection [16]	99	Porto	Before 1912
BoneMedLeg Collection [9]	95	Porto	1969–2003

), the Identified Skeleton Collection of IUCS-CESPU (CEIC, Coleção de Esqueletos Identificados da CESPU) being the tenth.

Cardoso [7] divided human skeletal collections into three types, depending on the source of their skeletons:

(1)

Unclaimed cadavers, often used in Medical Schools for teaching anatomy and dissection, which usually include some of the oldest reference collections in the world;

(2)

Body donations, which can be included in the former, as well;

(3)

Historic or modern cemetery remains.

For forensic purposes, most of the collections used in Southern Europe and Latin America usually belong to the third described type. Yet not all these collections or methods derived from their analysis are suitable for forensic use. This happens since some techniques have been developed from regionally diverse, non-contemporary, and in part even non-identified skeletal samples, which limits their application to contemporary remains and remains that are temporally and spatially different from the methods’ reference samples [17]. Secular trends have been identified for several features of the biological profile [18,19,20]. Nevertheless, non-contemporary collections also remain important, as they can contribute to human variation understanding, and many of them include samples with well-documented traumatic, pathological, and taphonomical changes [17].

As forensic science expertise is becoming increasingly complex, a need for more recent collections has risen. The established measurements or parameters used for human identification methodologies have changed with time. The most suited collections for validating and adapting anthropological methods to regionally specific present-day forensic scenarios are contemporary (modern, i.e., with subjects born after 1920) documented collections, consisting of individuals with a fully or partially known biological profile [17].

To assemble such collections requires a methodologically rigorous procedure that can be used as an active learning approach, since it dynamically engages students with the subject being taught. This methodology differs from the traditional one, which relies on lectures, images, plastic models and/or already processed skeletal elements. In this manner, students hardly ever have a “real forensic experience”. This classical trend can be inverted by actively participating in the assembly of a given collection. This article aims to characterize and contextualize an example of such a process, showing how the assembly of a new collection of identified skeletons stored in the University Institute of Health Sciences, CESPU, is also being used as a pedagogical tool, with students actively involved in the cleaning, processing of the bones, and antemortem/postmortem information gathering, as well as in anthropology research projects.

2. The XXI Century CEIC Collection

The XXI century CEIC collection is being amassed from two cemeteries from Porto, in Portugal. So far, it comprises 98 individuals, 30 from Cemitério Prado do Repouso and 68 from Cemitério de Agramonte, and it is housed at the University Institute of Health Sciences—CESPU (Figure 1). Each box regards one individual removed by the cemetery services from a primary or secondary burial plot. Information regarding the individual was provided by the cemeteries, who gave us information about the persons’ name, date of (birth, date of death and nationality. This information was kept private.

The sample’s distribution by sex, according to the origin, is presented in

Table 2. Sample’s distribution of the XXI century CEIC (Coleção de Esqueletos Identificados da CESPU) collection, by sex, according to origin.

Cemeteries	Sex		Total
	Male	Female
Prado do Repouso	11	19	30
Agramonte	48	20	68
Total	59	39	98

.

So far, 41 skeletons have been fully processed. Students were involved in cleaning, marking, and bagging bones. First, boxes containing individual skeletons are carefully opened (Figure 2).

Then, bones are removed from the boxes and placed on a table covered with plastic foil (Figure 3).

Afterwards, each bone is carefully cleaned, using soft toothbrushes and stylets (Figure 4 and Figure 5).

After cleaning, bones are redistributed on the table and organized as closely as possible to their anatomical position.

Next, smaller bones, like those from hands and feet, are stored in bags identified with the collection acronym followed by the number given to the skeleton (Figure 6).

Conversely, bones with greater dimensions, such as the femur or the humerus, have the identification code written in a smooth area containing no relevant anatomical features (Figure 7). A steel nib pen and India ink were used. The number was applied to a layer of polish and left to dry. Then, a second layer was added. The polish was an acrylic water-based polish (Primal TM), that becomes transparent after drying.

In the second stage, students are asked to estimate the biological profile: ancestry, sex, age, and height. For estimating ancestry, they study the skull and retrieve cranial measures (Figure 8) that are then inserted and used in the software Ancestrees (available at http://lfa.uc.pt/ancestrees/, accessed on 4 September 2023) [21]. We know that other software could be used, but they all work in a similar manner, and this one was developed by a Portuguese research team, with which students can talk to and get engage in their own research projects.

For sex estimation, both the skull and pelvic bones are analysed. The students are given the following tables to provide an estimate (Figure 9).

The pelvis is analysed for age estimation applying Suchey–Brooks methodology [22] with students being given the following information for guidance (Figure 10).

Height is estimated using the length of the humerus or femur, applying the models developed by Mendonça et al. [23] (Figure 11).

The biological profile is then presented to a teacher who discusses the results with the students. The cemetery services provide information regarding each skeleton (usually, name, date of birth, date of death, sex, and nationality), which is kept private in a database not accessible to students. Usually, stature cannot be confirmed, as this data is unavailable. Yet, as we intend to create real forensic scenarios, we estimate this biological profile feature as well, as identifying someone can require stature estimation, and, in Portugal, these can be the actual methodologies used.

3. Discussion

The acquisition and curation of human skeletal remains for study are complex tasks that depend on compliance with ethical and technical criteria. With both fulfilled, they represent a unique opportunity in Forensic Sciences pedagogy and research. The hands-on approach is recognized as a valuable teaching methodology that produces amazing results in acquiring competencies [24], in processing human skeletonized remains and applying techniques for building the biological profile.

Much has been written about the ethical framework in the last few years since any forensic practice should abide by an ethical approach [25,26]. Cardoso [7] has argued that what has been written concerns mostly anatomy and donation-based collections, and not cemetery-based ones. These raise ethical concerns because it is unclear what approach should be followed with the so-called unclaimed remains. Alves-Cardoso [27,28] raised doubts about the legitimacy of considering the remains abandoned or unclaimed, questioning if every effort is being made to contact families, as many of the unclaimed may represent a poor and marginalized segment of society, lacking autonomy over their lives, without the opportunity or the option to exercise their rights. Cardoso [7] has underlined that these concerns address mainly consent about the removal of remains from the primary and secondary burials by cemetery authorities (which is done if the grave is abandoned, regardless of the faith of the remains) rather than consent about their subsequent use for scientific purposes. In Portugal, these concerns are undermined due to the approach followed. As for consent, Portugal has an opt-out body and organ donation system (RENNDA—National Registry for non-donors [29]), where individuals who have objected to the donation of their remains can be spotted and not-included in the collections. Another concern before incorporating a body in a collection relates to autopsied bodies since the municipality can only release these after judicial authorization [30].

As for technical issues regarding the origin, collections dating back to the 19th and 20th centuries may include body donations from hospitals, autopsies, or material gathered during explorative voyages around the world that resulted in non-homogeneous assemblages [17]. On the other hand, contemporary collections are usually accrued for forensic purposes. They are the product of collaborations between universities and local cemetery administrations or the result of body donation programs. For example, in our case, a cemetery-based collection, as the sources of the remains differ, the quantity and quality of information available from the collected remains also vary.

The cemetery-sourced collections, as is the one herein presented, often exhibit limitations regarding data collection, which can range from profiling errors (i.e., the sex of an individual based on the gendered name present on the tombstone) to incomplete or inaccurate data (i.e., missing or incorrect entries in the registries) [17], limitations that are not seen in other collections, namely the ones resulting from donations. Still, they represent a possibility for establishing new methodologies suitable for contemporary populations, and, as described, their assembly can be used as a pedagogical and research tool, presenting students with case-based methods and active learning approaches.

Innovative teaching methodologies present themselves as great opportunities to improve students’ achievements. Traditionally, lecturing has been the predominant mode of instruction since universities were established [31], and continues to have strong advocates [32]. Yet, some suggest that a constructive “ask, don’t tell” methodology may lead to better results in students’ performance, as the search for the information produces a more robust knowledge than just being told the answer [31]. This teaching strategy has already been reported as conveying the best results—for example, Freeman et al. [33] said that active learning increases examination performance and that lecturing increases failure rates by 55% in science, engineering, and mathematics courses. An active learning approach can be defined as a teaching methodology that actively engages students with the subject [24,34], such as the one presented. No results are yet available to compare students’ performances before and after implementing this strategy. Nevertheless, it is clear that there is greater class participation and enthusiasm, which hopefully will translate into better knowledge acquisition in Forensic Anthropology and Odontology.

When data is available regarding the details of a specific human remain, the students can discuss the results with a teacher and evaluate and compare what they infer to what is believed to be the ground truth. When differences occur, that represents an excellent learning opportunity, motivating them to further research methods and their limitations. For example, other methodologies could be used for the biological profile estimation, and teeth could also be used for sex or age estimation [35,36,37]. Thus, we are considering a broader approach to biological profile estimation, and we are currently developing a similar approach using teeth to estimate the biological profile.

Likewise, the collection has the potential to explore other dimensions of the osteological analyses relevant to the forensic field, namely paleopathology and trauma. In the future, similar projects focusing on these areas are thought to be developed.

4. Conclusions

Until now, Portugal had only nine human skeletal collections, six being classified as contemporary. Therefore, beyond the fact that it is housed in a university and has been used for pedagogical purposes in classes, providing students with unique learning experiences, this new collection also constitutes another fundamental tool for forensic anthropology and odontology research. This includes development and validation studies of skeletal ageing and sexing methods that target elderly adults, as well as, in conjunction with other national reference collections, the investigation of secular trends in skeletal development and ageing, among others. Thus, the XXI century CEIC collection is an important new pedagogical innovation and research tool for moving forensic science forward.