Modern Paleopathology, The Study of Diagnostic Approach to Ancient Diseases, their Pathology and Epidemiology: Let there be light, the light of science and critical thinking

ISBN-13: 9783031286230 / Angielski

Bruce M. Rothschild; Dawid Surmik; Filippo Bertozzo

Opis

The study of paleopathology has two very different constituencies, the medical scientist and the zoologist/paleontologist/anthropologist. Their investigative procedures and professional jargon are different, sometimes to the point of mutual incomprehensibility. Paleontologists/anthropologists/zoologists have a limited data base for the characterization and interpretation of pathology. This must come from the human and veterinary medical experience.

What, beyond intellectual satisfaction, can the health care community expect from this relationship? The past history of the appearance and dispersal of infectious disease and cancer is of considerable theoretical importance and leads to new insights on the nature and transmission of diseases that are otherwise ambiguous. The discovery of rheumatoid arthritis in pre-Columbian North America exemplifies insights gained.

The current effort delineates osseous impact of disease (as manifest in clinical populations diagnosed in life), representation in the zoologic, paleontologic and anthropologic record, and assessment techniques that can be confidently applied. The chapters form “columns” that provide the foundation for scientific critical thinking. The actual integration of the information is in its application. Our purpose is to provide a data base and atlas of actually documented skeletal impact of diseases (as population phenomenon), an initial data base of reported skeletal pathology, and a methodology for expanding this to new arenas.

The first section of the book examines the scientific basis of paleopathology, its transition from speculation-based musings, resolution of misconceptions and the denouement of paleo-epidemiology. The second section provides holistic analysis of the gamut of pathology/diseases with significant skeletal impact, with a validated archeologic/zoological/paleontological record. The third section provides a glossary to resolve the semantic challenges inherent to interdisciplinary efforts. The fourth section provides an atlas of pathology representation in the fossil record. Ultimately, this book intends to present a scientifically-validated approach to recognition of disease in the archeological, zoological and paleontological record, superseding previous speculation-based offerings.

Spis treści

I.                I. Scientific basis for paleopathology

 

   Chapter 1: Philosophy of Science

A.    Paleopathology as a science

B.    Origins of paleopathology

C.    Transition from speculation to science

1. Speculation approach

2.     Diagnostic nihilism

D.    Actualism

1.     Intrinsic, contextual and inferential considerations

2.     Pathology speaks for itself

3.     Vetting premises

4.     Reproducibility and bias in study samples

5.     Cultural/Geologic context

E.     Theoretical/philosophical considerations

1.     Fundamentals of a scientific approach

2.     “Spectral” diagnoses

3.     The testable hypothesis

4.     Collaborative approaches, learning curves and semantics

5.     Understanding controversy

F.     Application of scientific methodology

1.     Establishment of criteria for disease recognition

2.     Paleoepidemiology

3.     Documented reproducibility

4.     Data base

G.    Behavioral inferences

H.    Denouement

 

   Chapter 2: Osseous structures and their response repertoire

A.     The nature of bone

1.     The nature of growth

2.     Cortical and trabecular bone

a.      Bone structures and types

1.     Lamellar bone

2.     Woven bone

3.     Metaplastic bone

4.     Dermal bone

5.     Medullary bone

6.     Pachycephalosaurus skull lesions

b.     Periosteum

c.      Bone atrophy

d.     Epiphyseal clefts

B.    Osseous structures of biologic origin and their mimics

1.     Antlers

2.     Enamel

3.     Dentine and dermal bone healing

C.    Bone response to” stress”

1.     Density

2.     Osteosclerosis and hyperostosis

3.     Limited or focal hyperostosis

4.     "Growth arrest" lines – actually growth restoration lines

5.     Size and shape

a.      Expansion

b.     Bowing

D.    Pathologic alterations of bone

1.     Remodeling

2.     Cribotic bone alterations

3.     Erosive disease

4.     Peri-lesional alterations

5.     Osteolysis

6.     Periosteal reaction

7.     Cortical hyperostosis

8.     Enthesial reaction

9.     Bone ankyloses/fusion

10.  Vertebrae are special

a.       Osteophytes and shape variation

b.     Lumbar lordosis and vertebral shape

c.      Hemivertebrae

d.     Vertebral endplates

1.     Defects

a.      Surface deposits

b.     Schmorl’s nodes

c.      Linear defects

d.     Zoologic/Paleontologic record

11.  Hips are special

a.      Cribra femora

b.     Allen’s fossa

c.      Herniation pit

d.     Impingement syndrome

e.      Poirier’s facet

f.      Femoral plaque

12.  Ballooned bones

E.     Variations on a theme

   Chapter 3: Documentation of preservation

1.     Petrification/ossification semantics

2.     Nonosseous structures

3.     Extra-skeletal phenomena and their mimics

a.      Uroliths

b.     Gallstones

c.      Bezoars

d.     Regurgitatites

e.      Gastroliths

f.      Coprolites

g.     hydatid (Echinococcus) cysts

h.     Uterine fibroids

i.       Thyroid nodules - calcified goiter

j.       Calcified tissue nodules

k.     Calcified lymph nodes

l.       Renal masses

m.   Gastrointestinal disease-related calcifications

n.     Intervertebral disk calcification

o.     Lithopedian

p.     Teratoma

q.     Myositis ossificans

r.      Fibrodysplasia ossificans progressive (FOP)

s.      Calcific masses of unclear derivation

4.     Soft tissue preservation

a.      Structures

b.     Skin

c.      Red blood cells

d.     Parasites

e.      Diet and gastrointestinal content

f.      Trackways

5.     Microscopic preservation

6.     Mummies

7.     Molecular preservation

a.      Protein

b.     DNA

c.      Lipids

8.     Denouement

   Chapter 4: Postmortem alterations of bone (Diagenic Changes) and their interpretation

A.    The challenge

B.    Mechanical and meteorological factors

C.    Biologic factors

D.    Chemical factors

E.     Denouement

  Chapter 5: Misconceptions and false trails

A.    Illusion

1.     Porosity, a phenomenon in search of significance

2.     Location of cortical bone alterations within or on a bone

3.     Melanoma diagnosed on basis of color changes

4.     Ochronosis, where technique and logic collide

5.     Observations without controls

B.    Apparently lack of reliability of testing

1.     Bone density

2.     Blood group

3.     Misunderstandings of clinical medicine

C.     Apparently untestable

1.     Rheumatoid factor

2.     Histocompatibility antigen (HLA)-B27

D.    Unfounded notions

1.     Untested criteria

2.     The myth of the osteological paradox

3.     The myth that disease-induced bone alterations documented in known afflicted individuals cannot serve as models for general recognition of disease

4.     The myth that disease-induced bone alterations observed in humans

           cannot serve as a models are comparable to that in other species.

5.     The myth that disease-induced bone alterations alter sufficiently over time  

     to preclude comparison with observations in modern individuals.

6.     The myth of osteological manifestations of iron deficiency

7.     The external appearance of normal cortical bone

8.     The myth of nonspecific periosteal reaction

9.     The myth of sphenoid porosity identification of scurvy

10.  The mythology related to interpretation of enthesial changes

11.  The mythology of cranial suture fusion as measure of age

12.  The evolution of virulence

13.  Conflating interpretation with observation

14.  Assumption that presence of pathology implies impairment

15.  Conflating severity and disability

E.     Questionable  approaches – Superficiality

1.     Taking attributes at face value

2.     Failure to validate

3.     Limited differential diagnostic considerations

4.     Application of statistical techniques

5.     The scapegoat/strawman

6.     Apparent attempt to obviate inconvenient evidence

F.     Bias

G.    Resolution

   Chapter 6: Diagnostic approach/techniques

            A.  Macroscopy and surface imaging

            B.  Radiologic techniques

                        1.Theory

2. Standard x-ray technique

3. Fluoroscopy

4. Xeroradiography and its replacement for edge enhancement and increased

resolution

5. Magnification radiography

6. Tomography

7. Computerized tomography

8. Synchrotron imagery

9. Micro-CT

                        10. Magnetic resonance imaging

                        11.  Three-dimensional imaging and dissection

                        12.  Special considerastions

                                    a.  Sacroiliac joints

                                    b.  Zygapophyseal joints

                                    c.  Sinuses

            C.  Microscopy

1.  Direct light microscopy

2.  Raman/infrared spectroscopy

                        3.  Immuno-microscopy

                        4.  Electron microscopy and x-ray diffraction

                        5.  3-Dimensional imaging

            D.  Molecular techniques

                        1. DNA

                        2. Protein identification, proteomics and isotope analysis

                        3. Lipids

                                   

II.             Holistic analysis of pathology/diseases with significant skeletal impact

 

   Chapter 7:  Mechanically-derived phenomena

1.     Trauma-related

a.      Direct and indirect evidence

b.     Bone bruises and other trauma-related bone evidence

c.      Bite, claw and horn injuries

d.     Exostoses

e.      Osteochondroma

f.      Osteochondritis and Osteochondrosis

g.     Schmorl’s nodes

h.     Fractures

1.     Epidemiology

2.     Mechanisms

3.     Greenstick fractures

4.     Vertebral fractures

5.     Pilon and impact fractures

6.     Spondylolisthesis

7.     Implications

8.     Spontaneous osteonecrosis

9.     Fracture healing

10.  The zoological/paleontological record

i.       Stress fractures and plastic deformation

1.     Nature

2.     Epidemiology

3.     Appearance

4.     Differential diagnosis

5.     The zoologic/paleontology record

6.     Fibrodysplasia ossificans progressiva

j.       Enthesial phenomena

k.     Tendon avulsions

l.       Diffuse idiopathic skeletal hyperostosis and ligamentous ossification

a.      Axial skeleton

b.     Peripheral skeleton

c.      Significance

d.     Differential diagnosis

e.      The anthropologic/zoologic/paleontology record

2.     Osteoarthritis

a.      Semantics

b.     Nature of disease

c.      Differential diagnostic consideration

d.     Recognition of osteoarthritis

e.      Eburnation as a source of confusion

f.      Pathophysiology

g.     Misdirection

h.     The anthropologic record

i.       The zoologic/paleontologic record

j.       Erosive osteoarthritis

k.     Neuropathic arthritis

l.       Disability

m.   Denouement

n.     Speculations as to behavior implications

   Chapter 8: Inflammatory arthritis

A.    Rheumatoid arthritis

1.     Rheumatoid erosions

a.       Rheumatoid erosions

b.     Character

c.      Distribution

d.     Reproducibility

e.      Differential diagnosis

2.     Validation of the rheumatoid arthritis recognition in defleshed bones

3.     Anthropologic aspects of rheumatoid arthritis

4.     Diagnostic confusion – the lumper-splitter controversy

1.     Distinguishing criteria

2.     Biomechanical evidence

3.     Archeologic record

4.     Subgroup comparison

5.     Nature of Erosive Arthritis in Animals

5.     Pseudo-rheumatoid – unsubstantiated diagnoses

6.     The Archeological record

7.     Absence of a Zoological/Paleontological record

B.    Spondyloarthropathy

1. Nomenclature

2. Character

3. Ankylosing spondylitis and inflammatory bowel disease

4. Psoriatic arthritis, reactive arthritis and undifferentiated forms

5. Differential diagnostic considerations

6. The Archeologic record

7. The Zoological/Paleontologic record

      a. Trans-phylogenetic distribution

      b. Epidemiology

8. Denouement

C.    Juvenile arthritis (Juvenile rheumatoid arthritis/Juvenile inflammatory arthritis)

1.  Nature of disease

                                    2.  Osteology

                                    3.  Differential diagnosis

2. Juvenile spondyloarthropathy

3. Archeologic/Zoologic record

D.    Gout

1. Nature of disease

      2. Character

      3. Skeletal distribution of lesions

      4. Population prevalence and predisposition

      5. Differential diagnosis

      6. Anthropologic record

      7. Zoologic/Paleontologic record

E.     Calcium pyrophosphate and hydroxyapatite deposition disease

1.     Character

2.     Axial disease

3.     Erosion mimics

4.     Pseudo-rheumatoid manifestations

5.     Primary versus secondary

6.     Alternative interpretation of deposits on bone

7.     Differential considerations

8.     Archeologic record

9.     Zoologic/ Paleontologic record

 

   Chapter 9: Infectious disease

10.  Neutrophilic and Heterophilic-responsive infections

a.       Character

b.     Radiology

c.      Histology

d.     Differential diagnosis

e.      Archeologic record

f.      Zoologic/Paleontologic evidence of infectious disease

g.     Melioidosis

h.     Erysipelothrix

11.  Sinus infections

12.  Chronic Recurrent Multifocal Osteomyelitis

a.      Character

b.     The Archeologic record

c.      The Zoological/Paleontological record

13.  Special considerations

a.      Actinomyces, the branching, acid-fast bacteria

b.     Brucellosis

c.      Plague

d.     Trachoma

e.      Osteoperiostitis

14.  Mycobacterial disease

a. Non-lepromatous mycobacterial disease

1. Mycobacterium tuberculosis

2. Mycobacterum bovis

3. Atypical mycobacterium

4. Tuberculosis mimics

a. Tuberculosis-like findings in the paleontologic record

b. Sarcoidosis

b. Mycobacterium leprae

8.  Fungal disease

a.      Character

b.     The Archeologic record

c.      The Zoological/Paleontological record

8.     Treponemal disease

a.      Character of disease

b.     The data

c.      The preconceived notion

d.     Reproducibility of findings

e.      Pinta

f.      Distinguishing among the Treponematoses

g.     Ancillary issues

h.     Differential diagnosis from non-treponemal disease

i.       Treponematosis – anthropology-related considerations

j.       North America

1.     The data

2.     Alternative perspective

k.     South American and the Caribbean

l.       Documentation of existance at site of Columbian contact - prior to Columbus

m.   Africa

n.     Europe

o.     Asia and Asian Pacific

p.     Zoologic/Paleontologic record

11. Parasitic infections

            a. General

            b. Trichomonas

                                    c. Echinococcus

                                    d. Malaria

                                    e. Ticks

                                    f. Archeologic record

                                    g. Zoologic/Paleontologic record

12. Viral disease

13. Evolutionary misconceptions of infectious disease

14. Evolution of infectious disease.

 

   Chapter 10: Hematologic

1.     Bleeding disorders

2.     Anemia

a.      Porotic hyperostosis and the myth of it attribution to iron deficiency anemia

b.     The obverse - Iron deficiency produces hypoplastic marrow

c.      Absence of skull changes from documented primary iron deficiency

d.     Fallacy of skeletal recognition of iron deficiency

e.      Deficiency-derived anemia

f.      Hemolytic anemia

1.Overlooked hemolytic anemia

2.Thalassemia

3.Marrow proliferation in thalassemia perforates the cortex, eroding

tubular and flat bones

4.Sickle cell anemia

3.     Archeologic record

4.     Paleontologic record

   Chapter 11:  Metabolic/Endocrine

1.     Harris growth lines

2.     Osteoporosis

3.     Growth hormone overproduction

4.     Growth hormone underproduction

5.     Thyroid disease

6.     Hyperparathyroidism

7.     Hypoparathyroidism

8.     Miscellaneous endocrine disorders

9.     Thiamine and Niacin (Pellagra) deficiency

10.  Hypervitaminosis A

11.  Hypovitaminosis A

12.  Vitamin C deficiency- scurvy

a.      Osseous manifestations

b.     The falsified sphenoid porosity speculation

c.      Documented archeologic cases

d.     Suggested cases that likely have other explanations

e.      Documented zoologic/paleontologic cases

13.  Vitamin D deficient activity- osteomalacia and rickets

14.  Renal osteodystrophy

15.  Leontiasis ossea

16.  Homocystinuria

17.  Hyperphosphatasia

18.  Hyperphosphasia

19.  Hypophosphatemia

20.  Osteosclerotic diseases

a.      Osteopetrosis

b.     Melorheostosis

c.      Paget’s disease of bone

d.     “Osteoperiostitis”

21.  Liver disease

22.  Iron storage disease

23.  Copper storage disease

24.  Copper deficiency

25.  Molybdenum toxicity

26.  Ochronosis

27.  Infiltrative diseases

a.       Hyperlipoproteinemia

b.     Multicentric reticulohistiocytosis

c.      Lysosomal storage diseases

1.     Gaucher’s disease

2.     Mucopolysaccharidosis

3.     Gangliosidosis

4.     Mucolipidosis

5.     Mannosidosis

6.     Niemann-Pick disease

7.     Membranous lipodystrophy

8.     Farber’s lipogranulomatosis

9.     Miscellaneous

28.  Amylodosis

29.  Mast cell disease

30.  Manganese deficiency

31.  Pancreatic disease

32.  Metabolic/Toxicologic diseases associated with increased bone density

a.      Oxalosis

b.     Fluorosis

c.      Bismuth-related

d.     Silicosis

e.      Mercury-related

f.      Lead-related

33.  Congenital

a.      General

b.     Dwarfism

c.      Teratology

d.     Klippel-Feil syndrome

e.      Arthrogyposis

f.      Miscellaneous

g.     Artheologic record

h.     Zoologic/Paleontologic record

i.       Epiphyseal abnormalities

j.       Homeobox disorders

1.     General

2.     Axial skeleton

a.      Segmentation disorders

b.     Shape modification

c.      Schmorl’s nodes

d.     Slipped femoral epiphyses

e.      Scheuermann’s disease

f.      Spina bifida

3.     Third metatarsal-tarsal joint

4.     Coalitions

5.     Fused carapace or plastron

6.     Inherited osteosclerotic phenomenon

a.      General

b.     Melorheostosis

34.  Pregnancy-related issues

 

   Chapter 12:  Vascular phenomena

1.     Hemangiomas and vascular anomalies

2.     Aneurysms

3.     Vascular considerations related to red blood cell size

4.     Bone infarcts

5.     Avascular necrosis

6.     The Archeological record

7.     The Zoologic/Paleontologic record

 

   Chapter 13:  Bone neoplasia and skeletal dysplasias

1.     Peto’s paradox

2.     Skeletal dysplasia

3.     Bone cysts

4.     Bone islands

5.     Osteogenic bone tumors

a.      Osteoma

b.     Hamartoma

c.      Osteoblastoma

d.     Osteosarcoma

6.     Cartilaginous bone tumors

a.      Chondroma

b.     Enchondroma

c.      Chondroblastoma

d.     Chondromyxoid fibroma

e.      Chondrosarcoma

7.     Fibromas

8.     Adamantinomas

9.     Giant cell tumors

10.  Ewing sarcoma

11.  Soft tissue sarcomas

12.  Chordromas

13.  Vascular tumors

14.  Lipid cell tumors

15.  Liposclerosing myxofibrous tumor

16.  Histiocytic tumors

17.  Neurofibromatosis

18.  Leukemia and lymphoma

19.  Multiple myeloma

20.  Waldenström’s macroglobulinemia

21.  Metastatic cancer

22.  Hypertropic osteoarthropathy

23.  Mandibular masses

24.  Archaeological record

25.  Zoologic/Paleontologic record

 

   Chapter 14:  Cranial phenomena

1.     Fronto-parietal pores

2.     Marrow hyperplasia – porotic hyperostosis

3.     Frontal bossing

4.     Sinusitis

5.     Cholesteatoma

6.     Otitis media

7.     Cribra orbitalia

8.     Pressure phenomenon

9.     Skull defects attributed to parasite

10.  Caries sicca

11.  Endocranial impressions and Serpens Endocrania Symmetrica

12.  Cranial hyperostosis

a.      Hyperostosis Frontalis Interna

b.     Meningioma

c.      Cranial hemangiomas

13.  Parietal thinning

14.  Externaul auditory exostoses

15.  Dental

 

Chapter 16. Glossary

 

Human and veterinary medicine, paleontology and anthropology share a common language, often quite disparate in meaning.  This section provides the clarification so essential to interdisciplinary efforts.

 

Chapter 17.  Case studies

1.     A point in time

2.     Angulated vertebral column

3.     Anomalous anomaly

4.     Articular surface defects

5.     Beware taphonomy

6.     Chasing ghosts

7.     Excavated vertebrae

8.     Hats off

9.     Holey skull

10.  It’s not acne

11.  Lion face

12.  Location, location, location

13.  Lumpy joints

14.  Pressure phenomenon

15.  Recognizing trees in the forest

16.  Saber shin deformity

17.  The striation neologism

18.  Ticks and fleas

19.  To be or not to be

20.  What doesn’t belong

Whittling and fusion

O autorze

Bruce M. Rothschild graduated from New Jersey College of Medicine.  He is a member of the Society of Vertebrate Paleontology, Fellow of the American College of Physicians, American College of Rheumatology and Society of Skeletal Radiology and elected to the International Skeletal Society.  He has been recognized for his work in Clinical Rheumatology and Skeletal Pathology where his special interests focus on diagnosis, clinical-anatomic-radiologic correlation, data-based paleopathology, evolution of inflammatory arthritis and infectious disease and origins of disease.  Dr. Rothschild is Professor of Medicine at IU Health and holds a Research Associateship at the Carnegie Museum. 

He has been Professor of Medicine at Northeast Ohio Medical University in Rootstown, Ohio, Adjuvant Professor of Anthropology at the University of Kansas and of Biomedical Engineering at The University of Akron, Ohio and Research Associate at the Biodiversity Institute of the University of Kansas and the Carnegie Museum of Natural History. He was the first director of the Rheumatology Division at The Chicago Medical School and a prime force behind the resurgence of data-based paleorheumatology and comparative osseous pathology. 

He has been a visiting Professor at universities in the US, Canada, the Caribbean, South America, Europe, the Middle East, South Africa, Asia and Australia and has been an invited lecturer at universities, hospital and museums throughout the world.  He has published over 1000 papers and abstracts, including authoritative papers on bone maturation, the origins of rheumatoid arthritis, spondyloarthropathy, syphilis, tuberculosis, character of bone changes in metastatic cancer, myeloma, leukemia, tuberculosis, fungal disease, renal disease, treponemal disease, rheumatoid arthritis, spondyloarthropathy, gout, calcium pyrophosphate deposition disease, hypertrophic osteoarthropathy, primate bone disease and critical thinking not limited to paleopathology.  He is the author of 7 books and has participated in 8 Discover Channel/BBC documentaries on origins of diseases and ancient reptiles.

Dawid Surmik graduated from the University of Silesia in Katowice, Poland, where he pursued

his entire academic career from B.Sc. to a doctorate, and where he currently works as an

assistant professor and researcher. He is a vertebrate paleontologist by education with special

interests in evolutionary biology, paleoecology, and taphonomy. He became interested in

paleopathology in 2016 when he accidentally identified an intriguing bone alteration in the fossil

material he was studying. Then he started collaborating with Professor Bruce M. Rothschild,

who was his mentor in the field, and with whom he began collaborating on subsequent projects.

 

In 2019, he received financial support from National Science Centre, Poland for the research

project “;Osteopathologies in the fossil record as a vector of paleoecological and

paleoepidemiological information,” the frame in which he studied pathologies of Triassic

marine reptiles from Germanic Basin, terrestrial Triassic tetrapods from Krasiejów, Poland and

dinosaur pathologies from Gobi Desert, Central Mongolia. Dawid believes that the prevalence

of diseases in animal populations sheds light on biosphere stress and is one of the most important

factors influencing the survival of organisms in nature.  Traces of diseases in the fossil

material provide a deep and multilevel understanding of the processes governing the evolution

of life on Earth. In particular, he thinks that examination of the occurrence of cancer in various

extinct animals will expand our knowledge of the evolutionary biology of neoplasms.

 

He is the author of several dozen publications including abstracts and scientific papers. He is the

reviewer and editorial board member of several respected scientific magazines. He collaborates

closely with several European research institutions, in particular with the University of Bonn,

Germany, where he is an associate researcher.

Filippo Bertozzo is a postdoc researcher at the Royal Belgian Institute of Natural Science in Brussel (Belgium). He studied in Italy, obtaining an undergrad diploma at the University of Bologna with extensive work on the ornithopod Ouranosaurus nigeriensis, and later a Master in Science at the Universität Bonn, Germany, with an analysis on the histology of pneumatic bones in sauropod dinosaurs.  He graduated at Queen’s University Belfast -under the Horizon 2020 Program of the Marie-Curie Foundation- in 2021. His doctoral dissertation was aimed to identify and diagnose paleopathologies in ornithopod dinosaurs from the Northern Hemisphere, incorporating the data into an epidemiological approach to understand pathological trends and patterns, especially in iguanodontian dinosaurs. He combines traditional analysis (osteology, histology) to 3D imaging techniques (microCT analysis and digitization) to decipher behavioral aspects from paleopathological trends.  He is a member of the Society of Vertebrate Paleontology, the Canadian Society of Vertebrate Paleontology, the Palaeontological Association, the Società Paleontologica Italiana and the European Association of Vertebrate Paleontologists. He is an associate researchwe of the Sociedade de Historia Natural in Torres Vedras, Portugal. He collaborated with the Natural History Museum in London (UK), the Royal Tyrrell Museum of Paleontology in Drumheller and the Royal Ontario Museum in Toronto (Canada). He participated in fieldwork in Spain, Portugal, Germany, US (Nevada, Wyoming), Canada (Alberta), far eastern Russia and Niger.