Quantifying animals' physical capabilities
Dec 4, 2022 0:08:54 GMT 5
elosha11 and theropod like this
Post by Supercommunist on Dec 4, 2022 0:08:54 GMT 5
So math and jargon aren't my strong suit but I thought it would be cool to have a thread where we collect hard data on animal's physical capabilties. Given that zoology doesn't get much funding and its hard to measure an animal's maximum physical capabilities without subjecting them to abuse, I don't expect to gather much but I hope to pleasantly surprised
www.nature.com/articles/s41598-017-02161-w#MOESM1
Had to download the dataset to find this.
Cat muscle fibres generate roughly 3 times more power than humans.
www.ncbi.nlm.nih.gov/pmc/articles/PMC3587382/#:~:text=The%20highest%20specific%20force%20in,4C%29.
Lions and cheetahs have about 20 percent higher muscle fibre than zebras and impalas.
www.nature.com/articles/nature25479
Contrary to popular media chimpanzees are not 5x stronger than humans.
www.ncbi.nlm.nih.gov/pmc/articles/PMC5514706/#:~:text=Our%20results%20show%20that%20chimpanzee,force%20or%20maximum%20shortening%20velocities.
This study suggests that whales are rather weak compared to terrestrial animals.
onlinelibrary.wiley.com/doi/abs/10.1111/mms.12230
Here is a laymans article on the subkect that no longer works:
www.bbc.com/earth/story/20150529-the-strongest-whale-in-the-world
Another site managed reposted the article.
acsmb.org/wp-content/uploads/2015/06/Soundings1506.pdf
Not sure I buy the difference in strength being that dramatic. I wonder if the study's methods were somehow biased against aquatic animals.
Table S1: Muscle modelling parameters used to predict bite forces in BHI 3033 based on volumetric
rendering of soft tissues from a CT scan of an articulated 14.45% skull replica. Values for
muscle length were derived using the protocol from [35], and left-right averages were used here;
muscle volumes were derived using the material properties feature of Avizo Lite for 3-D rendered
muscle bellies and left-right averages were used here; each muscle volume was dived by 1.056 g/cm3 to
account for non-contractile tissues; adjusted muscle volumes and lengths were used to calculate physiological
cross sectional areas (PCSAs); a standard value of Alligator mississippiensismuscle stress (32.4 N/cm2 [35])
was used to convert PCSAs for each muscle into a maximum value of contractile muscle force; using the
dimensions of each muscle from the Avizo Lite model, the verticle (Y-axis) component of
mucsle force was isolated for each muscle belly; these values were used to calculate muscle
moments, using average values of left and right muscle in-lever lengths and a recruitment value
of 100% for all jaw adductors; the subsequent values were then doubled to account for the
contralateral side jaw adductor muscle moments; estimated muscle moments for all jaw-
closing muscles were then summed and divided by the distance from the jaw joint to the bite
point (out-lever) for each tooth position of interest. The maximum Y-axis contractile muscle forces
were then scaled based on specimen size to provide muscle forces for the skulls of the other
adult Tyrannosaurus rex specimens sampled in this study (see Table S2 B). (See main text and Figure 2 for
abbreviations.)
rendering of soft tissues from a CT scan of an articulated 14.45% skull replica. Values for
muscle length were derived using the protocol from [35], and left-right averages were used here;
muscle volumes were derived using the material properties feature of Avizo Lite for 3-D rendered
muscle bellies and left-right averages were used here; each muscle volume was dived by 1.056 g/cm3 to
account for non-contractile tissues; adjusted muscle volumes and lengths were used to calculate physiological
cross sectional areas (PCSAs); a standard value of Alligator mississippiensismuscle stress (32.4 N/cm2 [35])
was used to convert PCSAs for each muscle into a maximum value of contractile muscle force; using the
dimensions of each muscle from the Avizo Lite model, the verticle (Y-axis) component of
mucsle force was isolated for each muscle belly; these values were used to calculate muscle
moments, using average values of left and right muscle in-lever lengths and a recruitment value
of 100% for all jaw adductors; the subsequent values were then doubled to account for the
contralateral side jaw adductor muscle moments; estimated muscle moments for all jaw-
closing muscles were then summed and divided by the distance from the jaw joint to the bite
point (out-lever) for each tooth position of interest. The maximum Y-axis contractile muscle forces
were then scaled based on specimen size to provide muscle forces for the skulls of the other
adult Tyrannosaurus rex specimens sampled in this study (see Table S2 B). (See main text and Figure 2 for
abbreviations.)
www.nature.com/articles/s41598-017-02161-w#MOESM1
Had to download the dataset to find this.
Cat muscle fibres generate roughly 3 times more power than humans.
On average, the felid type IIx fibres produced significantly greater force (191–211 kN m−2) and ~3 times more power (29.0–30.3 kN m−2 fibre lengths s−1) than the human IIax fibres (100–150 kN m−2, 4–11 kN m−2 fibre lengths s−1). Vmax values of the lion type IIx fibres were also higher than those of human type IIax fibres. The findings suggest that the same fibre type may differ substantially between species and potential explanations are discussed.
Absolute force produced by lion and caracal type IIx fibres was lower (P<0.05) than that of human type IIax fibres, but once corrected for CSA, the muscle fibres of both wild animal species produced significantly more specific force than human fibres (Fig. 4B,C). The two type I fibres produced an absolute force of 0.21±0.02 mN and a specific force of 162±9.9 kN m−2. Although statistical power is weak (N=2 for lion), the specific force of lion type I fibres appeared to be ~2.5-fold greater than their human equivalent.
www.ncbi.nlm.nih.gov/pmc/articles/PMC3587382/#:~:text=The%20highest%20specific%20force%20in,4C%29.
Lions and cheetahs have about 20 percent higher muscle fibre than zebras and impalas.
We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator–prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey.
Muscle biopsies were skinned, placed in a trehalose–glycerol mixture, frozen in liquid nitrogen in the field and transported to the United Kingdom. Peak power, velocity and stress at peak power and maximum isometric stress were determined at 25 °C for single, skinned fibres (Fig. 2a–f). Maximum power and associated velocity and stress were then calculated (Methods). Complete measurements were made on 37 individual skinned fibres from six cheetahs, 30 fibres from five impalas, 50 fibres from eight lions and 57 fibres from eight zebras. There was a distinct subpopulation of ‘low-performance’ fibres (twelve fibres from zebra, eight fibres from lions, three fibres from cheetahs and three fibres from impalas; Fig. 2d–f and Supplementary Data) with a velocity at peak power that was below 1.35 lengths s−1 and a lower peak power (Fig. 2c and Extended Data Fig. 2g), which were either myosin heavy chain (MHC) type-I (11 of 19 fibres tested) or type-II (8 fibres) (Methods). Linear mixed-effects models were fitted for peak power, velocity and stress at peak power and isometric stress with a factor distinguishing predator and prey, including the interaction of this factor with a categorical variable called ‘fibre performance classification’. Within the factor distinguishing predator and prey, we nested a random effect by subject and fibre. The residuals of this model exhibited heteroscedasticity and so the variance of the error term was allowed to vary by subject and performance classification. Power in the high-performance fibres was 20% greater in the predator group than in the prey group (effect size=20.0 W kg−1 , z=−3.46, P= 0.001). The difference was similar in both pairings. However, the effect was significant only in the lion– zebra pair (effect size=20.0 W kg−1 , 20%, z=2.56, P=0.039), but not in the cheetah–impala pair (effect size= 18.9 W kg−1 , 19%, z= 2.04, P= 0.15). The peak-specific powers were very similar in the two predator species, and lower but very similar in the two prey species (mean power of high-performing fibres± standard error in W kg−1 : cheetahs, 106.7± 4.6; lions, 108.1± 4.2; impalas, 88.3± 5.2; zebras, 88.4±4.1). No significant differences between predators and prey were detected for the velocity at peak power (effect size 0.096 lengths s−1 , z=−1.77, P= 0.15) or stress at peak power (effect size= 7.2 kPa, z= −2.05, P=0.075) for high-performance fibres. Isometric stress was higher in predators (effect size=33.4kPa, z=−2.87, P=0.008; Extended Data Fig. 2). The values reported here are comparable to data for skinned fibres from wild rabbits at 25 °C22, but are high compared to published values for skinned fibres from large animals23,24. Muscle power is highly temperature dependent25 and a temperature coefficient (Q10; the ratiometric increase in rate with a temperature increase of 10°C) of 2.3 is appropriate26, which predicts in vivo muscle power (all fibres, Extended Data Fig. 2i) of 232 (prey) and 292 (predators) W kg−1 at a body temperature of 38°C. Slower myosin types and muscle fibres are inherently more economical23,25,27, thus slower fibres confer advantages25, and the fast versus slow distribution of fibres reflects the opposing pressures of predation (avoidance) on one side and food and water supply, ranging distance and environmental conditions on the other25,28. This may partly explain why prey species have lower-power muscle fibres25. Therefore, muscles of desert specialists at risk of dehydration and/or starvation29, such as camels, vicunas and Arabian oryx, would be predicted to be biased towards economy25. Selection pressure for greater performance or economy could change fibre type distributions or muscle characteristics within a few generations—much more rapid than for changes in myosin contractile speed.
www.nature.com/articles/nature25479
Contrary to popular media chimpanzees are not 5x stronger than humans.
Our results show that chimpanzee muscle exceeds human muscle in maximum dynamic force and power output by ∼1.35 times. This is primarily due to the chimpanzee’s higher fast-twitch fiber content, rather than exceptional maximum isometric force or maximum shortening velocities.
www.ncbi.nlm.nih.gov/pmc/articles/PMC5514706/#:~:text=Our%20results%20show%20that%20chimpanzee,force%20or%20maximum%20shortening%20velocities.
This study suggests that whales are rather weak compared to terrestrial animals.
onlinelibrary.wiley.com/doi/abs/10.1111/mms.12230
Here is a laymans article on the subkect that no longer works:
"Overall, though having greater absolute strength, large whales aren’t that strong relative to their size when compared to some land animals. For example, an elephant, the largest of the terrestrial mammals, cited by the study had a total body mass of 2,500 kg. It produced a force while running of 27 kN. “A young minke whale has a similar total body mass but is calculated to produce a force of only 6.4 kN,” says Mr Logan. “A buffalo had a total body mass of 500 kg and produced a force of 12 kN. In comparison a small pilot whale is calculated to produce only 2.7kN of force.” “The difference in force output between the terrestrial and marine mammals illustrates a fundamental difference in the kinds of selective pressures these animals are exposed to,” Mr Logan told BBC Earth. Land animals need to use their skeleton and muscles to support their body mass against the force of gravity, for example, whereas marine mammals are supported by the buoyant force of water."
www.bbc.com/earth/story/20150529-the-strongest-whale-in-the-world
Another site managed reposted the article.
acsmb.org/wp-content/uploads/2015/06/Soundings1506.pdf
Not sure I buy the difference in strength being that dramatic. I wonder if the study's methods were somehow biased against aquatic animals.
