There is no doubt that plant species exhibit infinite practical utility, this time I wanted to refresh the entry and share with users of the platform #Hive especially as members of the community #STEMsocial, linking plant species with the procedures for collection, analysis and presentation of evidence in scientific investigations of forensic and criminal investigations. As in previous editions, the post is presented in a clear and accessible way, without renouncing the methodical rigor of the article, in the search to improve the understanding of the subject in specialist and non-specialist botanical users.
Plant species are essential for the existence of life, since they offer organographic structures rich in food substances, are a source of pharmacological, forestry and industrial raw materials, however, they are also characterized by providing information of technical relevance in the field of forensics and criminal profile investigations .
In this last instance, the value of plant species in a criminal investigation allows field professionals to use plants, organs, vegetative and reproductive segments within the analysis of the crime scene itself, by linking the recognition of botanical evidence and its relationship with the environment, vital elements for clarifying complex situations within this type of investigation.
Now, considering that there are few trained botanists who can help solve criminal cases that demand the use of plant species in field and forensic investigations, the objective of this post is to describe and conceptualize the botanical sub-areas related to plant evidence of forensic and criminal importance.
Forensic botany is the area of botany that offers anatomical, histological, dendrochronological, ecological, molecular, palynological, and limnological information, which prescribes usefulness as evidence within the techniques of forensic and criminalistic investigations.
It is important to mention that this discipline of botany is relatively new both on a national and international scale, the famous kidnapping and murder of the son of Charles and Anne Morrow Lindbergh in 1935 being the first legal case where botanical information was accepted as promising evidence for the resolution of a crime .
According to the biologist and researcher Jaffet M. Nassar, assigned to the area of ecology of the Venezuelan Institute of Scientific Research (Instituto Venezolano de Investigaciones Científicas), "the evidence that finally allowed incriminating the main suspect of this crime was a wooden staircase left in the Lindbergh house. A wood anatomy expert, Arthur Koehler, was able to identify four species of wood trees used in the construction of the staircase and detected an exact match between marks present in the wood and marks found on planks in the suspect's possession. The botanist's testimony set an important precedent for the admission of botanical evidence in other cases from that year onward in the United States.
Sub-areas of forensic application botany
Plant Anatomy and Histology
The study of the structures and external and internal organographic characteristics of plants is used in forensic botany to characterize and relate plant specimens to the places, or sites where the death or murder of one or more people occurred.
To determine the genetic specificity of the plant species or specimens found at the crime scene or victim's body, molecular biology is often used to identify the morphological features and DNA of the specimen.
Determining the age of the trees, by means of the growth rings or any alteration that may occur in the stem, is a tool that has been used in forensic botany, to help identify the pieces of wood, making them coincide with the scene of the crime.
Plant ecology studies how plants interact with their environment, therefore, it is used as a tool to locate clandestine tombs, allowing to determine if a certain site shows stages of succession different from the surrounding area, taking as an indication of a possible burial site.
In forensic botany, the detailed study of pollen grains in angiosperms and fern spores provides associative evidence, which can greatly help to find the place of death, decomposition and time of year.
Fig. 2 Flowers in full bloom of pollen grains that serve as botanical evidence in the forensic and criminalistic sciences to associate death or murder sites. Author: @lupafilotaxia.
Seasonal variation and diversity of unicellular algae is a sub-area of botany that is used in forensic investigations to profile time and compare specimens collected from body tissues to aid in the diagnosis of drowning and in the estimation of post-mortem interval.
Botanical evidence and forensic significance
The process for the clarification of a crime, where there is botanical evidence, is to ensure the collection and preservation of organographic structures, vegetative and reproductive segments found at the crime scene, which serve as support during forensic investigations aimed at providing answers to the causes that have led to death by suicide, or murder of a person.
Fig. 3 It is observed area with red piece of probable clothing, serves as evidence to associate people who frequented the site where a murder was committed. Author: @lupafilotaxia.
The most common practice that killers carry out after taking a person's life is to bury the body in wooded areas, parks, riverbanks, and backyards, among others. However, digging and burying a body affects the micro-ecosystem of the plant, because drowning alters the mechanical structure of the soil and the decomposition of the body breaks the balance of nutrients. Hence, the composition of plant communities is used as botanical evidence for the elucidation of this type of modus operandi. For this reason, when experts in criminalistics go to areas where one or more people are presumed to have been buried, they usually analyze the dynamic patterns of plant growth and development, and identify the area where the skeleton lies.
Fig. 4. Area where a man was found dismembered and buried in forest segments in Santa Bárbara del Zulia - Venezuela. Author: @lupafilotaxia.
Plant fragments and substances in the stomach
The analysis of stomach contents is a technique rarely used in criminal investigations, but is now recognized as a valuable source of information, because, since the introduction of forensic botany as an analysis tool, illustrative scenarios are allowed, which help clarify relevant points, focusing on the identification of ingested food, phytotoxic substances, psychoactive substances, movements, actions and places frequented by the victim hours before his death, such as restaurants, grocery stores, liquor stores, areas where drugs are distributed, discos and others.
Biogeographic and ecological contexts
Another common practice, perpetrated by unscrupulous people is to kill by throwing people from ravines, hills and mountain slopes, an action that provides enough information to field investigators and forensic professionals, to analyze traces and botanical deformations of the site where the crime occurred, determine the phases of the fall, as well as the dynamics of death by relating the blows and fractures in the body of the victim.
Fig. 5 Area with mouse tail seedlings observed (Achyranthes aspera). Author: @lupafilotaxia.
Similarly, after the murder has been consummated in a specific area and with the intention of misleading the criminal authorities, these people act by moving the body from the site where the atrocity was initially committed, thereby erasing the context and evidence.
Fig. 6 Reproductive organographic segments attached to clothing, plant material are hard and spiny flowers of Achyranthes aspera,, a species used as botanical evidence in forensic and criminal sciences. Author: @lupafilotaxia.
SCIENTIFIC CONTRIBUTIONS OF THIS PUBLICATION
- The technical descriptions related to the practical usefulness of plant species as scientific evidence of a forensic and criminalistic nature, highlight the main sub-areas of botany that provide useful information to clarify crimes and suicides that have occurred in complex scenes. In the next installments related to this botanical approach, I will present in detail reported cases, outlining the investigation process undertaken for their resolution.
BIBLIOGRAPHICAL REFERENCES CONSULTED AND CITED:
 Ferri G., Alù M., Corradini B., and Beduschi G. Forensic botany: Species identification of botanical trace evidence using a multigene barcoding approach. Int J Legal Med. 2009; 123: 395–401. Article: Online access
 Jafet M. La Botánica como herramienta de la investigación criminal. Centro de Ecología del Instituto Venezolano de Investigaciones Científicas. S/F. Article: Online access
 Heather M., Cheng-Lung L., Wen-Yu L., Henry C., and Timothy M. Forensic Botany: Using Plant Evidence to Aid in Forensic Death Investigation. Croat Med J. 2005; 46; 4: 606-612. Article: Online access
 Fernández J., Galindo B., y Idrobo M. Las plantas como evidencia legal. Desarrollo de la Botánica Forense en Colombia. Rev. Acad. Colomb. Cienc. 2007; 31; 119: 181-198. Article: Online access
 Martínez M., Fernández S., y Carrión J. Palinología y escenario forense. Un caso de estudio del sureste de España. Anales de Biología. 2008; 30: 43-54. Article: Online access
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