Question

How do plant roots impact and influence bone destruction? What is root etching? Describe the ways plant roots contribute to destruction of skeletal remains. Often root etchings are mistaken for vascular channels – how might you distinguish between the two? What about cut marks from sharp force trauma?

What is acidic soil corrosion? What other taphonomic or destructive force on bone might acidic soil corrosion be confused with? How might you distinguish the two?

What causes bioerosion of microscopic structure in bone? Can we differentiate between the different agents? Do they attack the same regions of bone or different?

Consider our discussions on determining still-birth versus live birth of neonate remains. How might microbial bioerosion and presence or absence of the neonatal line provide evidence of live birth?

Summarize the changes in color as bone is exposed to thermal stress/fire? What are the two predominant processes and what color is indicative of each? Describe each state

Discuss the mechanics and molecular basis for fracture generation on bones of an articulated fleshed not decomposed body when exposed to thermal stress or fire. Why don’t we see the same fractures developing on wet/dry bone or already decomposing remains?

You have been asked to help in the recovery of completely skeletonized remains that were found buried in a shallow grave. The lead investigator suspects that the remains were moved and reburied in this grave. How might you distinguish between or what are some of the characteristics distinguishing primary burial from secondary burial?

What are the terms used to describe various scavenger bite mark damage on bone – are there consistencies across forensics or do individual FA just call the damage however they feel best describes it?

You are the lead FA and have been asked to lead a search and recovery effort to find a missing person. An informant has described the burial of this individual in a shallow grave in a meadow within a forest two summers previous. You believe you and your team have located the meadow. You will now direct the search. Summarize how you would organize the search and how your team members might recognize a clandestine grave?

Answer 1

How do plant roots impact and influence bone destruction?

Plant roots within soil can affect the chemical composition and cause mycohorrhizal root etchings on bone and cause physical destruction of bone.Acidic soil corrosion also can affect the bone surfaces in contact with the topsoil.These impacts can include changes in yield quantity and quality, timing of key developmental stages and tolerance of biotic and abiotic stresses.

What is root etching?

The root etching is produced by humic acids on the bone surfaces as a result of dissolution by acids with growth and decay of roots or fungus in direct contact with bone surfaces. They can be “dendritic” or “spaghetti like” patterns, which indicates that the bones were in a plant‐supporting sedimentary environment.The corrosion of the bone surface is associated with the plant roots, organic acids, and apparently high humidity of soils

Describe the ways plant roots contribute to destruction of skeletal remains.

Skeletal Remains is susceptible to plant root damage, although this will be strongly influenced by seasonal effects. Physical damage by plant roots can mark, warp, and even break bones.It is probable that plant roots manufacture mucilaginous substances that promote the growth of microorganisms when secreted. Certain microorganisms, including fungi, will discharge enzymes into the soil which catalyses the reaction that dissolves hydroxy-apatite in bone and facilitates its absorption into the plant root system. A low pH will promote these chemical changes. Plants and their root systems constitute complex physical and chemical processes that efficiently breakdown the external and internal structure of human bone.Acidic soil corrosion also can affect the bone surfaces in contact with the topsoil, although usually over less surface area than bones that were buried fully in acidic soil.Because bone is highly vulnerable to acidic attack pooling of acidic groundwater at the bottom of the coffin weakens the bones, and the pressure of the rest of the remains and possibly the collapsed lid and sediments above it crushes down on these weakened areas.

Often root etchings are mistaken for vascular channels – how might you distinguish between the two?

Root etchings pattern is meandering and branching with a U shaped surface whereas Vascular channels are the tunnels inside the bone with rounded edges following pattern of U/ V shaped and parallel striations on the surface.

What about cut marks from sharp force trauma?

The edge of the object creates a sharp force injury, characterized by cutting of the skin and underlying tissues, whereas the intensity of the force, or the relative "bluntness" of the object, results in associated abrasions, lacerations, and/or contusions, with or without underlying fractures resulting in cut marks

Acidic soil corrosion

Soils can have a wide range of acidity, reaching anywhere from 2.5 to 10. As pH levels of 5 or below i.e in acidity condition it can lead to extreme corrosion rates and premature pitting of metallic objects

What other taphonomic or destructive force on bone might acidic soil corrosion be confused with?

Corrosive agents can affect bone preservation and cause dissolution, breakdown, and loss of bone integrity. These effects may accrue over long intervals as with the corrosion and breakdown of bone in acidic soils and potentially in some aquatic environments. Soil acidity tends to affect all bone surfaces in contact with sediments and can lead to the formation of an irregular surface, thinning of margins, and even windowing where holes are formed in the bone . Digestion, including acidic attack and enzyme action, can have a major effect upon bone fragments or small whole bones, causing surface corrosion, sculpting, and windowing

What causes bioerosion of microscopic structure in bone?Can we differentiate between the different agents? Do they attack the same regions of bone or different?

Organisms involved in bioerosion of bone, mainly bacteria, fungi and cyanobacteria, create different types of alteration. While fungi and cyanobacteria dissolve the bone matrix resulting in branching tunnels, bacteria create microscopical focal destructions with a complex morphology, reorganising the mineral rather than removing it

Various agents are responsible such as bacteria,fungi etc .bacteria create microscopical focal destructions whereas fungi and cyanobacteria dissolve the bone matrix resulting in branching tunnels

Determining still-birth versus live birth of neonate remains

Stillbirth is typically defined as fetal death at or after 20 to 28 weeks of pregnancy . It results in a baby born without signs of life. The term is in contrast to miscarriage, which is an early pregnancy loss, and

live birth, where the baby is born alive, even if it dies shortly after

Determined by heart rate,LMP,gestational age, by fetal and neonatal deaths, such as perinatal mortality

How might microbial bioerosion and presence or absence of the neonatal line provide evidence of live birth?

The presence of neonatal line indicates live birth and it is possible to estimate the exact period of survival of the infant in days by measuring the amount of postnatal hard tissue formation, and thus can be an evidence to the brutal act of infanticide.