Smilodon populator

[LandSeaLion]

(04-27-2022, 01:57 AM)I’m Spalea Wrote: @GuateGojira 

About #108: " so cubs are allowed to eat even before the dominant male " . Unthinkable as concerns the pride of lions, even if, sometimes,  the males are able to leave the cubs eating before the females.

(04-27-2022, 02:08 AM)GuateGojira Wrote:

(04-27-2022, 01:57 AM)Spalea Wrote: About #108: " so cubs are allowed to eat even before the dominant male " . Unthinkable as concerns the pride of lions, even if, sometimes,  the males are able to leave the cubs eating before the females.

Correct, and that is something that is very interesting in tigers. This observations were made in Kanha and Ranthambore, thanks to its relativelly open habitat. In Chitwan it was not possible to check, habitat is too close for direct observations, except for baiting sites. Other behaviours like taking care of they cubs has been observed in Ranthambore and Panna and in the case of Chitwan, Sunquist found that the young adult M104 (previous to its independance) spend more time with its father M105 than with his mother or sister, although keeping a good distance most of the time. 

What I like the most is that tigers seems to recognize they relatives at some degree. Let's remember the case of the 9 tigers together in Ranthambore, the matriarc (oldest female ) with her cubs of that season, togheter with the dominant male of the area and her previous daughters and her cubs, a "tiger pride", and all of them ate in order, not fighting, all ate they part and the dominant tigress directed the entire activity. Valmik Thapar provided some of the most ground breaking observations ever!

It’s an interesting observation that ties into lions’ and tigers’ different growth strategies in the wild. The member “Acinonyx Sp” posted an interesting paper in the “Comparing Cats” thread recently that touched on this, in comparison with Smilodon fatalis (a cat that may have combined the growth strategies of lions and tigers):

https://www.sciencedirect.com/science/article/pii/S2589004220311135

Quote:The saber-toothed cat Smilodon fatalis is known predominantly from “predator trap” deposits, which has made many aspects of its life history difficult to infer. Here, we describe an association of at least two subadult and one adult S. fatalis from Pleistocene coastal deposits in Ecuador. The assemblage likely derived from a catastrophic mass mortality event, and thereby provides insights into the behavior of the species. The presence of a P3 in the subadult dentaries suggests inheritance, a rare instance of familial relatedness in the fossil record. The siblings were at least two years old and were associated with an adult that was likely their mother, indicating prolonged parental care in S. fatalis. Comparison with the growth of pantherine cats suggests that S. fatalis had a unique growth strategy among big cats that combines a growth rate that is similar to a tiger and the extended growth period of a lion.

'For example, high levels of sociality in S. fatalis have been considered plausible by some authors (Akersten (1985); Carbone et al. (2009); Christiansen and Harris (2012); Friscia et al. (2008); Gonyea (1976); Meachen-Samuels and Binder (2010); Van Valkenburgh and Sacco (2002)), but unlikely by others (Kiffner (2009); McCall et al. (2003)). Furthermore, it has been argued that S. fatalis would not have lived in polygynous groupings because of its putative reduced sexual dimorphism, but the possibility of social groups where polygamy or monogamy are the primary mating system cannot be discounted (Christiansen and Harris (2012); Meachen-Samuels and Binder (2010); Van Valkenburgh and Sacco (2002)).'

'At two years old, tigers (Panthera tigris) have been independent from their mothers for at least six months and weigh between 68% (males) and 94% (females) of their asymptotic body mass (Jones et al. (2009); Slaght et al., 2005). Meanwhile, two-year-old lions are nearly a year from independence and weigh from 58% (males) to 72% (females) of asymptotic body mass (Jones et al. (2009); Smuts et al. (1980)).'

(In captivity though, it’s a different story, as lions grow faster and reach puberty far earlier than their wild counterparts do. The difference in nutrition at an early age really makes a big impact!)

Quote:A major finding in this study was that captive male lions appear to reach puberty at a younger age than wild counterparts. Based on when males first show mounting behaviors, wild males reach sexual maturity at 2.2 years (26 months), but do not typically breed until they take over a pride at the average age of 4 [26,49] or 5 [23,50] years. Still, individuals as young as 3.3 years have been observed to control prides in the Serengeti and Ngorongoro Crater [11]. In wild lions, males 1.6–1.8 years of age were considered pre-pubertal because they produced lower serum testosterone than young adults and adults, weighed only ~88 kg, and were aspermic [11]. Histologic evaluation of testicular tissue from wild males further demonstrated that the onset of spermatogenesis begins at about 2.5 years of age (range: 2.2–2.8 years) [23]. Our study found that although the peripubertal age group had lower FAM concentrations compared to older age categories, the youngest males that tested positive for spermaturia were 105 kg at 1.2 years of age.

The growth kinetics presented in the present study indicate that captive-born lion cubs develop at a faster rate than wild-born cubs, which could account for the early puberty. Wild cubs are heavier for the first few months after birth, but between 3–5 months of age the growth patterns were the same to our captive cubs. Both captive and wild cubs begin to taste/consume meat a few months after birth and are usually weaned by 0.5 years [22,27,50]. However, after weaning, the plane of nutrition appears to diverge between wild- and captive-born cubs and the ADG rate is no longer synchronous, perhaps a result of feeding captive cubs meat daily. There is substantial variability in growth rate in wild African lions [22], and the rate at which lion cubs grow is correlated with food availability once they are weaned [50,51]. Cubs are dependent on adults for food [7,22], but when prey is scarce, young lions go without food for extended periods [50–52] and starvation is a common cause of death at that age [7,22,53]. Captive cubs likely experience an early onset of puberty and reach adult body weight earlier as a result of the consistent feedings they are provided [22,50,54]. For most mammals, the onset of puberty is associated with attaining a threshold body weight [55–59] and acquiring adequate fat reserves [60]. Under-nutrition can delay onset of puberty while over-conditioned animals often attain puberty at an earlier age.

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