Functional morphology and behaviour Flashcards
Looking evidence in modern spcecies to interpret the past: Bat ear example
- Bat ear echo location structure (fossil same to extant species)
- Know from this that past bats also echo-located
Why are goats unusual ?
Wouldn’t be able to guess how good at climbing they are based on their body structure
Notes about fossil reconstruction
- Can reconstruct using different individual fossils that overlap
- Closer an organism is to living representative the easier to reconstruct
- Living relatives are highly modified (birds)
- Use anatomical knowledge based on nearest living relatives (crocs or birds)
What can ‘Fleshing up the dinosaur’ tell us?
- Use rare soft tissue preservation
- Use knowledge of nearest living relatives (crocodiles)
- Biomechanical knowledge - can input 3 dimensional model of skeleton and manipulate it to see where muscles would have most likely been attached
- Calculate size of muscle needed
How do Biomechanics help us understand how dinosaurs moved etc?
- Tells us about the capabilities of the dinosaur
- How strong/fast etc
- Use 3D computer animations based on engineering algorithms to infer details of dinosaurs
What do ‘trackways’ show us?
- Dimensionless speed
- Can work out distance between footprints and distance from foot to hip bone
- Can work out max speed, walking speed etc
Examples of speeds of dinosaurs worked out from trackways
- Small bipedal theropods and ornithopods:- 40 km/hr
- Large bipedal theropods and ornithopods:- 20 km/hr
- Quadrepedal stegosaurs and ankylosaurs:- 6-8 km/hr
- Quadrepedal sauropods:- 12-17 km/hr
- Quadrepedal ceratopsians galloping:- 25 km/hr
How can we work out the Intelligence of dinosaurs?
- EQ analysis
- Brain to body mass
- Sauropodomorpha - small brain compared to body ratio (low intelligence)
- Herd groups had more intelligence - combat predation
- Theropods - varied brain size to body ratio - hunters so higher intelligence.
- Dromaeosaurs: small but very large brain size to body ratio. Most intelligent group of dinosaurs - sister group to the birds.
How can we work out the diet of dinosaurs?
- Preserved stomach contents, coprolites etc
- Tooth form gives the best clue as to what they eat
- Sharp = meat
- Grinding teeth - vegetation
- Coprolites show what the organism ate but not where the coprolite came from
What do jaw adaptations show us about diet?
- Hinged jaws in hadrosaurs allowing sliding movement for certain grinding teeth.
- Hinge in cheekbone also allowed same movement in ornithopod
- Two different ways of creating a side swing
- Evidence they ate vegetation
Co-occurence
- What was eating what (who was eating who)
- Work out food webs
what do fortuitous finds tell us?
- Give us insights in to life histories of dinosaurs
- E.g. Velociraptor/Protoceratops death lock. Perfect preservation of one attacking the other
Can we work out the behaviour of dinosaurs?
- Difficult to work out
- Egg laying - if bones are not-ossified in fossilised embryos the organism probably had parental care - brooding.
What can fossilised footprints show us?
- Many animal tracks together - migration
- Hunting behaviour
What can we tell about the physiology of dinosaurs ?
- Bone structures
- E.g. Pachycephalosaurus headbutting (sexual dimophim, used in male competition?)
- Can estimate systolic blood pressure (sauropod double the pressure of giraffe)
How did the dinosaur stance an activity levels give evidence for THERMOREGULATION?
- Bipeadal / fast moving
- Would need lots of energy for this
- High energy output needs thermoregulation
How does adaptations for processing high volumes of food show evidence for thermoregulation?
- Teeth give evidence for processing high volumes of food
- Difference in the amount of food warm and cold extant animals need
- Warm blooded eat much more food
How does haemodynamics give evidence for thermoregulation?
How heart is made up
Crocodile hearts have been misinterpreted
How does brain size give evidence for thermoregulation?
- Brain size: larger brains suggest warm blooded, the brain takes up a lot of thermal energy.
How does nose morphology give evidence for thermoregulation?
- Nose morphology more complecated
- Suggests they were warm blooded
How does bone histology and Growth rates give evidence for thermoregulation?
Structures within bones
How does Predator-prey ratios give evidence for thermoregulation?
Processing large amounts of food etc
How does palaeogeogrpahy give evidence for thermoregulation?
Polar dinosaurs - must have lived through polar winters, would have needed to be warm blooded.
How does Core and peripheral temperatures give evidence for thermoregulation?
Look at isotopic ratios of bones
Stegosaurus plates, What were they for ?
- Basal lineages had spines for defence
- Plates evolved later
- Thermoregulation, vascularised plates?
