Movement and Biomechanics Flashcards
1
Q
Why do animals move:
A
- Food
- Reproduction
- Predator avoidance
- Environmental conditions
2
Q
Consequences
A
- Movement of organisms is a fundamental feature of life.
- Movement is central to almost all ecological and evolutionary processes.
- Affects survival, reproductive success and influences structuring of populations, communities and ecosystems.
3
Q
Movement definition
A
- A physical displacement over time.
- Movement takes place in continuous time, but we usually observe and study it in discrete time.
4
Q
Range in body size and movement speed.
A
Huge size range of motile organisms
5
Q
Size v speed
A
- Bigger animals tend to be faster, power law relationship.
- Cost of transport decreases with increasing body mass
- Animals are limited in their time for maximum acceleration because of restrictions on the quickly available energy.
6
Q
Biologging:
A
- Animal attached remote sensing, deployment of autonomous recording tags on free-living animals.
- Environmental parameters.
- Physiological parameters
- Movement parameters
- Behavioural parameters
7
Q
Geographic location tags
A
gps
argos satellite
geolocations
8
Q
GPS
A
- Determines an animal’s position.
- Error ranges between 20 and 50m.
- Typically, archival/retrieve device to get data
9
Q
- Argos Satellite (PTT):
A
- Device that communicates with polar-orbiting Argos satellites to determine its location.
- Error ranges between 500m and 10km.
- Transmits data.
10
Q
- Geolocator (GLS):
A
- Measures light levels and accurate time, which can be used to determine geographic location.
- Error range between tens and 100s of kms
- Archival.
11
Q
For smaller animals tracking
A
- Use of acoustic tags.
12
Q
Tag less tracking:
A
- Animals need to be captured.
- Tags are too heavy/large in relation to animals.
- Tags can be expensive.
- Track from video.
13
Q
Diel Vertical migration:
A
- Daily migration for light of phytoplankton.
14
Q
predators to find food:
A
- Area restricted search.
- Predators search more thoroughly for food in some areas.
- Theory predicts that for a predator, searching for prey with a patchy distribution:
- After encountering prey, should slow down and increase its turning angles to try and remain in the prey patch.
15
Q
Modes of movement:
A
- Unicellular organisms can be accomplished by changing shape using sliding elements in the cytoskeleton.
- Many organisms use flagella.
- In most cases, forces are generated by contraction forces.
16
Q
Ciliary structure and function:
A
Cilia and flagella, cylindrical array of 9 filaments within which a microtubule extends into the cilium and a partial microtubule which don’t extend as far.
* Cross-bridges of dynein extend from complete microtubule of one filament to the partial microtubule of the adjacent filament.
* 9+2 arrangement, pair of microtubules down centre.
17
Q
Sliding filament model:
A
- Strong parallels between this and cilia.
- Powered by ATP
- Dynein like myosin is the ATPase.
- Regulated by calcium ions.
18
Q
Metazoan muscle:
A
- Muscle contractions are powered by ATP.
- Muscle forces usually act on some type of skeleton.
- In the vertebrates, muscles attach to, and work in conjunction with a bony internal skeleton.
- In hard bodied invertebrates’ muscles attach to exoskeleton.
19
Q
- Muscle contraction:
A
- Myosin head split ATP, myosin binds to ATP and forms cross bridges.
- Myosin moves forward toward centre of sarcomere.
- Myosin attaches to ATP and crossbridge detach.
20
Q
Hydrostatic skeletons:
A
- In soft bodied invertebrates, muscle layers act on a hydrostatic skeleton.
- The segmentation in annelids act like boiler stays, allowing the musculature to exert much greater pressure.
21
Q
Metazoan swimming:
A
- Cilia and flagella, protozoa, macroalgal gametes, larvae and some meiofauna.
- Wave-like undulations, many worms.
- Fluid propulsion, medusoid coelenterates, cephalopods and pectinid bivalves.
- Use of flattened appendages, some decapod crustaceans, fish, cetaceans and pinnepeds
22
Q
locomotion
A
- Same structure used simultaneously accomplish multiple functions.
- Crustaceans may use rhythmic movement for walking and gas exchange.
- Female brine shrimp combine swimming gas exchange and irrigation of their ovisac.
23
Q
Evolution in locomotion:
A
- As a result of convergent evolution, species in diverse taxonomic groups may use the same pattern of locomotion
24
Q
Moving through sediment:
A
- Broadly divided into hard bodied diggers such as crustaceans.
- Echinoids and soft bodied burrowers that include some coelenterates, molluscs, and representatives of all the vermiform taxa.
- Small group of specialised drillers that can bore through soft rock and wood.
25
Q
Reynolds number - Moving through water:
A
- Organisms whose movements are described by low Reynolds numbers (<10) create laminar flows in their wakes.
- Their movements are mainly affected by viscous drag that retards forwards progress.
- A low Reynolds number organism must continually work to keep moving.
- Organisms with a high number >200000 tend to be larger and faster moving.
- Create turbulent flows in their wakes.
- Turbulence produces low pressure than tends to hold them back, ‘pressure drag’ can be reduced by streamlining.
26
Q
Drag
A
- Gray’s paradox, power output insufficient for fish to swim at the fast speeds they achieve.
- Evolved adaptations to improve their hydrodynamic efficiencies.
- Dolphin skin delays water flowing over skin and becomes turbulent, reducing drag
27
Q
Drag on sharks:
A
- Frictional drag is the most important source of drag in fast-swimming fish, such as sharks.
- Caused by the friction created between the skin and the boundary layer.
- can be reduced if the boundary layer maintains a turbulent flow.
- All fast-swimming sharks have sharp-edged riblets on their skin created by the denticles in their skin.
- absorb some turbulence between the denticles, and the sharp edges allow surface vortices to break away easily.
28
Q
Biomechanics of staying still:
A
- For many sessile species their habitat requires that they resist mechanical forces that dislodge them.
- Shape and ribbing of the base plate of the test increases the adhesion of a protein glue that is coded for the same gene that contributes to clotting agents associated with mammalian erythrocytes.
