A total of 14 individuals (11 Indian wolves and three Woolly wolves) were captured, radio-collared, and monitored from 2015 to 2021 to understand the movement, space use, and habitat preferences of two wolf lineages (Table 1). The Woolly wolves were captured in Himachal Pradesh and Indian wolves in Maharashtra, states of India. These wolves were captured using soft leg-hold traps. The traps (n = 25) were placed in a circular setup (radius = 70–80 cm), placed ∼20 cm apart from each other and tied with each other using rope (Habib, 2007). The wolf gland lure No. 100 (Stanley Hawbaker and Sons, Fort London, Pennsylvania) was used to attract the wolves toward traps. We also used fresh scats collected from different areas considering the scats were of different packs and placed around the traps to attract the wolf. The traps were connected to GSM-based device called “MinkPolice.” This device operates with a magnetic switch and triggers a message on the registered email and phone numbers. Trapped wolves were held using double threaded nylon hockey net. The captured wolves were immobilized by injecting Ketamine–Xylazine (dosages based on the weight of the captured wolf) intramuscularly on their hind leg (Habib, 2007; Habib et al., 2021a). The immobilized wolves were fitted with 10 iridium, 3 Globalstar and 1 VHF collars.

Data on the diet of both the wolf lineages were collected from published sources using specific keyword searches in Google scholar such as Tibetan wolf, Tibetan wolf diet, Himalayan wolf diet, Woolly wolf diet, Canis lupus chanco, Indian wolf diet, Indian gray wolf diet, Canis lupus pallipes. We found seven studies (two from India, three from Nepal, and two from Pakistan) to understand the Woolly wolf. For the Indian wolf diet, we found seven exclusive diet studies from Maharashtra, Gujarat, and Bihar States of India.

To understand the food habits of the Woolly and Indian wolves, we collected published data from different sources (detail provided in Supplementary Table 1). Different studies presented results in various forms, such as absolute frequency and relative frequency. To reduce the effect of study-specific variability, we first calculated the number of food items in the number of scats (Supplementary Tables 2, 3) and then calculated the relative frequency of occurrence (%RFO).

So far, there are two published studies on the howling parameter of the wolves from the Indian sub-continent (Hennelly et al., 2017; Sadhukhan et al., 2019). Hennelly et al. (2017) compared the vocalization of multiple wolf populations across the world, including the Woolly wolf and the Indian wolf and Sadhukhan et al. (2019) characterized the vocalization of the Indian wolves exclusively. Both the studies used nine parameters, such as mean frequency, maximum frequency, minimum frequency, frequency range, and end frequency, to understand the howling behavior of these two lineages. In these studies, the acoustic data were collected in the Trans-Himalayan region for Woolly wolf and Maharashtra for the Indian wolf.

The data on cranial morphometry of 14 Woolly and 20 Indian wolves were obtained from three studies, Allen (1938), Pocock (1941), and Srinivas and Jhala (2021). Data on total length (maximum length of skull from tip of rostrum to the nuchal crest); condyle basal length (distance from posterior projection of the occipital condyles to the anterior edge of pre-maxillary bones); zygomatic width (distance between outermost points of zygomatic arches), mandibular length (the distance from the jaw bone between the lower incisor of the anterior border of condyle); interorbital width (least distance between anterior orbits); post-orbital width (least distance between posterior orbits) and maxillary width (distance between the central fosse of the right and left first maxillary molars), PM4 (Pre-molar 4) and M1 (molar 1) were compared to understand the differences between the two subspecies (Supplementary Figure 1). The details of studies used for comparative ecological perspectives are provided in Supplementary Table 1.

The movement patterns of wolves were assessed using parameters such as daily average displacement (straight-line distance between two consecutive fixes) and average displacement during day and night. The varying inter-fix intervals were made uniform by post-processing all the data into an hourly data format (Abrahms, 2015; Habib et al., 2021a). Average displacement during the day and night were calculated by classifying locations. Average displacements of both the lineages were compared using the Wilcoxon rank sum test. Home ranges were calculated using minimum convex polygon (MCP) and Brownian bridge movement model (BBMM) (Horne et al., 2007). To understand the habitat preferences of Woolly and Indian wolves the landuse data for the states of Himachal Pradesh and Maharashtra were acquired from Bhuvan’s open-source website (NRSA, 2016).¹ Habitat use and preference of the Woolly and Indian wolf lineages were analyzed using Manly’s resource selection function (Manly et al., 2002). The design-III study framework of habitat use, where the animals are identified individually and both the use and the availability are measured for each one, was applied (Thomas and Taylor, 1990). The data on “use” was calculated from the number of GPS fixes and “availability” of land-use categories was calculated within the 100% MCP home range. All the measurements of movement parameters and analyses were carried out using ArcMET tool (Wall, 2014) in ArcGIS 10.6 and package “adehabitatLT,” version 0.3.25 (Calenge, 2015a) and animal movement tool (amt, version 0.1.3) (Signer et al., 2017) in program R 4.0.3 (R Core Team, 2021). Habitat use analysis was performed using the package “adehabitatHS,” version 0.3.15 in the program R, version 4.0.3 (Calenge, 2015b; R Core Team, 2021). For the comparison of cranial measurement of Woolly and Indian wolf we used two sampled unequal variance T-test and hedge’s g test to evaluate the effect size.

We combined the food items consumed in all the studies to represent the overall diet of wolves in the landscape and calculated the relative frequency of occurrence (RO) of each food item. We tabulated the RO of each item (number of occurrences of each prey item in scats/total number of scats × 100). We categorized the food items into wild and domestic prey and also in the body-weight classes (0–10 kg small prey; 11–70 kg medium-sized prey; >70 kg large prey) to compare the food habits. The details of studies used to comprehend the feeding habits of the two subspecies is provided in Supplementary Tables 2, 3.

A total of 47,240 fixes across 13 individuals (five males and eight females) of the wolves were analyzed (Table 1) to examine daily movement, movement during day and night time, space use, and habitat use. The average hourly displacement of the Indian wolf (527.68 ± 111.52 m/hr) was significantly (W = 29, p = 0.01) higher than the Woolly wolf (338.54 ± 34.82 m/hr). The mean hourly displacement during the day for Indian wolf (393.71 ± 172.43 m/hr) and Woolly wolf (316.70 ± 18.7 m/hr) was not significantly different (W = 12; p = 0.6). However, the mean hourly displacement during nighttime was 53% higher for the Indian wolf than the Woolly wolf and the result was significantly different (W = 28, p = 0.02) (Figure 1).

We evaluated the home range and core area sizes of both the lineages (Woolly wolf n = 3; Indian wolf n = 10) to compare the space use (Figure 2). The Woolly wolf home range was significantly larger (1689.80 km², range 827.54–3055.45 km²) than the Indian wolf home range (212.26 km², range 4.92–981.48 km²) based on 95% MCP (W = 1; p = 0.01). The core area (50% MCP) for the Woolly wolf was also larger (352.71 km², range 273.18–477.51 km²) than that of the Indian wolf (20.37 km², range 0.53–51.05 km²) (Figure 3). The 95% BBMM of the Woolly wolf was significantly larger (374.17 km², range 283.93–422.17 km²) than that of the Indian wolf (130.86 km², range 4.7- 399.56 km²) (W = 3; p = 0.04). The core area (50% BBMM) for Woolly wolf was also larger (37.74 km², range 37.74–28.37 km²) than the Indian wolf (13.07 km², range 0.63–54.43 km²), but values were not statistically significant (W = 4; p = 0.07) (Figure 3).

Resource selection function revealed a preferential selection for landuse categories by the Woolly wolf (Khi2L = 77.26, df = 6, p < 0.001) and the Indian wolf lineages (Khi2L = 520.3487, df = 35, p < 0.001). While riversides, marshes (valley habitat) (Wi = 6.44 ± 3.86SE) and scrub forests (Wi = 2.58 ± 3.39SE) were preferred by the Woolly wolf whereas the Indian wolf preferred grassland areas (Wi = 2.86 ± 0.37SE) and plantations (Wi = 2.71 ± 1.25SE). Builtup and agriculture areas were very less used in proportion to its availability by both the wolves (Figure 4A). In addition, the Woolly wolf and the Indian wolf avoided snow cover and waterbodies, respectively (Figure 4B).

Hennelly et al. (2017) suggested that the Indian wolf exhibited higher mean frequencies (593.5 Hz ± 211.4SE), wider frequency ranges (197.1 Hz ± 137.4SE), and longer duration (2.71 s ± 2.11SE) based on 117 howl recordings. On the other hand, 301 howls of the Woolly wolf characteristically had a lower mean frequency (428.5 Hz ± 125.7SE), shorter duration (2.56 s ± 1.68SE), and unmodulated frequency variation (101.8 Hz ± 107.1SE) (Table 2). In contrast to Hennelly et al. (2017), the Indian wolf howl parameters reported by Sadhukhan et al. (2019) were broader in range and overlapped with the howling parameters of the Woolly wolf (Table 2). Sadhukhan et al. (2019) reported 422.2 Hz ± 126.40SE mean frequency and longer duration 5.21 s ± 2.49 for the Indian wolf howl (Table 2). Sadhukhan et al. (2019) collected data on 238 howling records of the Indian wolves from Maharashtra, in the same landscape where Hennelly et al. (2017) collected their samples of 117 Indian wolf howls.

We found seven studies exclusive on the diet of Woolly wolf covering the Himalayan region in India, Pakistan and Nepal. There were 20 different items (Supplementary Table 2) reported in Woolly wolf diet from 869 scats with 124.14 (± 190.94 SD) scats per study. The relative frequency of occurrences (RO) in scats for wild prey, domestic prey and vegetative matter were 41.93, 48.44, and 6.46%, respectively. The RO in scats of Woolly wolves for large, medium and small-sized prey were 32.32, 33.87, and 24.18%, respectively (Figure 5A). About 70% of the Woolly diet consisted of goat, marmot, blue sheep, and pika, with a major contribution of cattle.

Another seven studies exclusively on the diet of Indian wolves from Rajasthan, Bihar and Maharashtra states of India revealed 17 different prey items from 6,877 scats with 982.42 (± 1363.67 SD) scats per study (Supplementary Table 3). The RO in scats for wild prey, domestic prey and vegetative matter was found 49.32, 40.34, and 9.31%, respectively. The Indian wolf diet primarily consisted of 67.95% of medium-sized prey followed by small (13.65%) and large-sized prey (7.15%) (Figure 5B). 75% of food items consisted of blackbuck, goat, sheep and hare in the Indian wolf diet with the major contribution of livestock.

We re-examined the data and compared the morphological differences between the two sub species. We found a significant difference between the two subspecies in the total length of the skull (p = 0.004; hedge’s g = 2.15), condyle basal length (p = 0.003; hedge’s g = 1.21), zygomatic width (p < 0.001; hedge’s g = 1.31) and mandibular length (p = 0.04; hedge’s g = 1.002) (Figure 6A), interorbital width (p < 0.001; hedge’s g = 1.79), post-orbital width (p < 0.001; hedge’s g = 1.12), maxillary width (p = 0.001; hedge’s g = 1.29), pre-molar4 (p < 0.001; hedge’s g = 1.52), and molar1 (p < 0.001; hedge’s g = 1.65) (Figure 6B).

The home range of Woolly wolf (95% MCP) was found eight times larger than the Indian wolf home range. Moreover, the extensive use area within the home range (50% MCP or core area) of the Woolly wolf was 17 times larger than the core area of the Indian wolf home range. The difference between the home ranges of these two lineages narrowed down in home range estimation by the advanced method of BBMM. The 95% isopleth of BBMM and 50% isopleth of BBMM of Woolly wolf were found only three times larger than those of the Indian wolf. The Woolly wolf resides in high-altitude rugged terrain areas with harsh climatic conditions. They usually used gentle slopes and valleys to move from one place to another (Lyngdoh, 2020), while MCP included cliff areas that the wolves could not use due to inaccessibility (Kenward et al., 2001; Silva et al., 2018). Different methods provided different information about home range size (Swihart and Slade, 1985; Gese et al., 1990; Silva et al., 2018). However, the MCP is widely used and can be useful to compare the home ranges of wolves from different studies. The BBMM provides reliable home range estimation, especially for central-place foragers and territorial carnivore species (Börger et al., 2008). This method is also reliable when the animals used several core areas or important travel corridors (Bullard, 1999; Horne et al., 2007; Kie et al., 2010).

Moreover, we also compared the home ranges and core areas of Indian wolf (MCP) with the previous studies and found that the home ranges in the previous studies were smaller (148.49 km²) (Jethva et al., 1997; Habib, 2007). The increase in the Indian wolf home ranges may probably be due to increased human pressure, habitat fragmentation, and prey depletion.

Large home ranges and core areas of the Woolly wolf could result from sparsely distributed prey species (Shrotriya et al., 2015) and suitable habitat continuity (Belongie, 2008). Wolves in mountainous regions selected low elevations, moderate slope and southwest aspect, probably to avoid snow cover and prey availability (Whittington et al., 2005). The home range for Mongolian wolves, which are closely related to the Woolly wolf, were among the largest home ranges (26,619 km²) of the wolves worldwide (Kaczensky et al., 2008). Kaczensky et al. (2008) argue that long-range seasonal shift in the used area could dramatically increase the overall home-ranges. Therefore, the reason of large home range of Woolly wolf may due to the seasonal variation of space use. In contrast, the Indian wolf is surviving in patchy, fragmented habitat within high human-dominated landscape. In such landscapes where wild prey is almost absent, factors such as the type and distribution of food resources, human interference, and topography may have played a significant role in determining home-range size. The human disturbance could also be the reason for having multiple core areas in Indian wolf, as they use small undisturbed patches for resting, mating, and rearing pups (Habib, 2007).

The mean displacement (m/h) of the Indian wolves was 35.2% higher than the Woolly wolves’ daily per hour movement. The daytime and nighttime displacement of the Indian wolves was 19.5 and 46.0% higher than the displacement of the Woolly wolf, respectively. The wolf is a widely distributed carnivore and its survival tactics involve a fine-tuned adaptation to local conditions. Their movement decisions are often the best functional compromise between finding food and avoiding humans (Ciucci et al., 1997). Some studies suggested that the wolf was primarily nocturnal in some areas, which allowed it to visit and move in intensive human-use areas without confrontation (Ciucci et al., 1997; Theurkauf et al., 2007). The Woolly wolf showed no difference between the day and night movement. In contrast, the Indian wolf movement aligned with the previous studies as their nighttime movement was almost twice the daytime movement. The no difference in the day night movement pattern of the Woolly wolf agreed with the findings of Vilà et al. (1995), who found that the wolf in Spain tended toward bimodal activity where nocturnality developed to cope up with human presence. Some studies suggested that wolves were most active during the night in summer (Fancy and Ballard, 1995) and during the daytime in winter (Mech, 1970).

As discussed above, the Woolly wolf home range was much larger than that of the Indian wolf. The functioning of the Woolly wolf in large home ranges but having less daily movement might be due to their use of valleys which makes the home range more linear, less compact, and larger. The higher movement of the Indian wolf in our study is in line with Daan (1981), who suggested a temporal shift in movement due to human disturbance. The other reason might be habitat fragmentation as the Indian wolves occupied fragmented areas, and the Woolly wolf inhibited continuous habitat. The results showed that the Indian wolf holds multiple core areas (Figure 2). Therefore, they need to travel more to find a secure area for resting and mating, as also supported by Ciucci et al., 1997. stated that the wolf activity mostly involved daily round-trip traveling from retreat areas to the core area of home ranges for some sort of social activity, which was also observed in previous studies (Carbyn, 1974).

Wolves are known as grassland and openland species (Pocock, 1941; Mech, 1970). While the Indian wolves clearly showed a preference toward the grasslands and used the grassland patches more than its availability, the Woolly wolves did not show much preference toward grassland and openland (included in the barren land category) and used it according to the availability. This is due to the high availability of openland in continuity in the Trans-Himalayan region. The Woolly wolf showed an affinity to the riverside and marshes (valley habitat), which is energetically economic travel routes along with the refuge areas. Moreover, these areas are often also more sheltered from the harsh conditions inclusing cold wind. Avoidance of waterbodies by the Indian wolf could be better explained by the association of water presence with the proximity of humans in the peninsular Indian landscape. Both the wolves showed avoidance toward human-influenced areas such as agriculture and builtup more strongly so in the case of the Indian wolf. Paquet et al. (1996) found that mountain wolves did not have many options to avoid humans due to the selection of valley habitats which is often used by humans. The Indian wolf also faces higher human pressure than the Trans-Himalayan population because of the higher human population density in plains than in the Trans-Himalayan region (Mishra et al., 2009).

Based on published literature, we compared the magnitude and pattern of howl acoustic structure to evaluate whether the long-range vocalizations showed acoustic differences between two wolf lineages in India. It is well understood that howl characteristics vary among different wolf subspecies (Kershenbaum et al., 2016). Due to the unique features of high amplitude and low frequency, a howl can travel for six kilometers or more and can be used to identify individuals for population estimation (Sadhukhan et al., 2021). Hennelly et al. (2017), compared the differences in the howls of the Himalayan wolf (aka Woolly wolf), Indian wolf, North African wolf (now African golden jackal; Sarabia et al., 2021), and Holarctic clades. The study found that small wolf subspecies, North African, Indian, and Israeli wolf had higher mean frequencies than the large wolf subspecies. Hence the body size could affect acoustic parameters.

In contrast, the study by Sadhukhan et al. (2019) reported lower mean frequencies for the Indian wolf. The difference between the Woolly wolf and the Indian wolf howls in Hennelly et al. (2017) could be an artifact of sub-sampling bias as Hennelly et al., 2017 used 117 howl recordings. In contrast, Sadhukhan et al., 2019 used 238 howl recordings. Although both the studies sampled in the state of Maharashtra, yet their sampling years and locations varied. Both the studies sampled only a section of the Indian wolf population rendering the Indian wolf with a larger variation in mean frequencies overall.

Further, earlier studies have shown the similarities between the howls of various canid species and subspecies. Canis rufus showed similar howl type as coyotes Canis latrans, while European wolf (C. l. lupus) and Iberian wolf (C. l. signatus) howls were similar in signatures (Kershenbaum et al., 2016). The Indian wolf, Mackenzie Valley wolf (C. l. occidentalis) and Mexican wolf (C. l. baileyi) also showed similar howling signatures (Kershenbaum et al., 2016). The similarities in acoustic signatures between the two lineages may advocate the evolutionary history playing a role in howling behavior (Kershenbaum et al., 2016). We also second that canid howling is not an arbitrary signal but possesses species-specific information, reflecting that the adaptive processes of isolation or habitat features play a key role in howling behavior (Hennelly et al., 2017). Habitat and temporal variability might be the reason for different outcomes from the two studies. More studies are recommended to understand the differences in the howling parameters of these two lineages.

Wolves are pack hunters and are known to feed on a variety of different food items. They choose their prey based on availability, abundance, pack stability, season, and habitat accessibility in the human-dominated landscapes (Imbert et al., 2016; Lyngdoh et al., 2020). Our study revealed that the diet of Woolly wolf from the Himalayan region consisted of 20 different food items from small birds, reptiles to large mammals and domestic animals such as cattle and yak. A review study on the Woolly wolf dietary spectrum across their global distribution, including Tibet and China, reported 39 different food items (Lyngdoh et al., 2020). The energy requirement of large carnivores makes them prone to conflict with humans as they need a large prey base (Carbone et al., 1999; Mech and Boitoni, 2003). The Woolly wolf also consumed a sufficient proportion of the large-sized prey (32.32%) and medium-sized prey (33.87%) with a considerable quantity of small prey (24.18%) consumption in their diet (Figure 5). Various studies across the wolf distribution range confirm that large prey forms the major part of the wolf diet (Imbert et al., 2016; Mengulluoglu et al., 2019; Petridou et al., 2019; Sin et al., 2019). The dependency on small prey might be because of the scarcity of the large and medium-sized animals to avoid interactions with humans or to gain and fulfill energy requirements in the harsh climatic condition. The Woolly wolf is also heavily dependent upon the domestic prey items in the Himalayan region. Livestock (Yak, Dzo cow, Goat, and Sheep) were the most consumed mammals in the Woolly wolf diet compared to sparsely distributed wild prey. Hence, it is not surprising that Woolly wolf showed a marginal preference for domestic prey than wild prey. Many studies from the Trans-Himalayas accounted that low abundance of wild prey and poor management of livestock resulted in depredation by snow leopard and Woolly wolf (Jackson and Ahlborn, 1984; Mishra, 1997; Namgail et al., 2007; Anwar et al., 2012; Suryawanshi et al., 2013; Chetri et al., 2017).

Despite the Woolly wolf’s significant domestic animal consumption, they are being tolerated by the locals in some regions (Rangarajan, 2001; Lyngdoh et al., 2020). At the same time, they are persecuted in many areas for the same reason (Mishra, 1997). Apart from domestic animal consumption, major wild prey species were Asiatic ibex (Capra sibirica), Urial (Ovis vignei), Tibetan wild ass (Equus kiang), Tibetan argali (Ovis ammon hodgsoni) and Blue sheep (Pseudois navaur) (Anwar et al., 2012; Subba, 2012; Ahmed et al., 2017; Bocci et al., 2017; Chetri et al., 2017; Werhahn et al., 2019; Lyngdoh et al., 2020; Habib et al., 2021b). However, their combined contribution was as low as 16.77% of the total food items. It could be related to the small population size and sparse distribution of the ungulate species in the region (Shrotriya et al., 2015).

The Indian wolf also primarily preyed upon domestic animals, followed by wild prey items. The Indian wolf consumed a considerable amount of vegetative material (fruits and plant items, etc.), which was absent in the Woolly wolf diet. The absence of vegetative matter in the diet of the Woolly wolf may be due to the scarcity of wild fruiting plants in the Trans-Himalayan region or missed reporting in the studies due to difficulties in identification in the studies we reviewed in this study. The Indian wolf primarily preyed upon medium-sized mammals relating to the availability of blackbuck, chinkara, and especially livestock such as sheep and goat. The Indian wolf-bearing states (Rajasthan, Andhra Pradesh, Maharashtra, Telangana) have the highest goat and sheep population (20th Livestock Census: All India Report, 2019). The average pack size of the Indian wolf varied from 1.5 to 4.7 individuals in the breeding and non-breeding season (Kumar, 1998). The preference toward medium-sized prey could be due to the smaller pack size and body size of the Indian wolf. Small packs would require less food and find it difficult to prey upon large prey species. The studies used to understand the food habits were from different protection regimes, such as the protected area of Velvadar Blackbuck Sanctuary (Jhala, 1991) and the human-dominated landscape of Maharashtra (Habib, 2007). The diet of the wolves from Velvadar Blackbuck Sanctuary was dominantly comprised of wild prey base (91.8%), whereas Maharashtra wolves’ diet was dominated by domestic prey (47.8%). This shows that the wolf may prefer wild ungulates over domestic prey, depending upon the availability. Consequences of human-wolf conflict due to low prey abundance and unavailability can hinder conservation measures. Therefore, it is essential to address prey restoration and livestock security to reduce conflict and achieve better conservation management for wolves in the Himalayas and in the plains of India.

The Woolly wolf exists at 3,900–5,600 m elevation across the low-oxygen region of the Himalayas (Habib et al., 2013; Werhahn et al., 2018). Survival in such a landscape requires the Woolly wolf to face metabolic challenges such as severe oxidative stress and increased metabolic rates (Beall, 2007; Hassanin et al., 2009). Several studies have conducted a genetic analysis of the Woolly wolf, identified the genes facilitating their adaptation to cope with hypoxia (Zhang et al., 2014; Werhahn et al., 2018; Wang et al., 2020). However, their morphological adaptations against hypoxic conditions have not been paid much attention yet. Butaric and Klocke (2018) studied the adaptation of upper respiratory structures to hypoxic and cold dry air in humans occupying high and low altitudes. These adaptations in skull structures help in increased uptake and air conditioning processes. The Woolly wolf exhibited longer (total length) and broader (post and inter-orbital width) skulls than the Indian wolf. Hence, their skull size and structure could be an adaptation to meet respiratory demand of more oxygen (Butaric and Klocke, 2018). However, the wolves are known to conform Bergmann’s rule, that is the wolves in the northern latitude are generally larger in body size (Meiri et al., 2007).

The systematics of wolves from the Indian subcontinent is less studied, remains controversial and confusing regarding their taxonomic status as sub-species and species. Indian wolves gathered the interest of the scientific community for their unique evolutionary history and uncertain taxonomic status. Although the Indian wolf was first described by Hodgson (1847), a consensus on its nomenclature is yet to be reached after 175 years with several attempts made to clear their taxonomy (Aggarwal et al., 2003; Sharma et al., 2004; Werhahn et al., 2017; Alvares et al., 2019; Joshi et al., 2020; Wang et al., 2020, 2021). Hodgson (1847) described the Himalayan wolf as separate species, C. laniger, noting its appearances. Later, Blanford (1888) rejected Hodgson’s proposal and combined C. laniger with C. lupus, and elevated the Indian wolf to C. pallipes. However, after 50 years, Pocock (1941) described both the taxa as subspecies of C. lupus. In Pocock’s scheme, C. pallipes became C. l. pallipes, and C. laniger merged with C. l. chanco. Later on, more studies suggested the uniqueness of these two taxa and identified them as the oldest lineage of wolves but did not reach any conclusion (Sharma et al., 2004; Aggarwal et al., 2007; Werhahn et al., 2017). A recently conducted study of the Woolly wolf by Joshi et al., 2020 found no evidence for C. l. chanco to be distinct species. They suggested the acceptance of Woolly wolf as C. l. chanco and not as C. langier or C. himalayensis. Their findings were additionally supported by Wang et al. (2020), who found that wolves across the Himalayas and Tibetan plateau are closely related. The Woolly wolf adapted to survive in a low oxygen environment and the Indian wolf represents two of the most endangered wolf populations (Joshi et al., 2020; Hennelly et al., 2021; Wang et al., 2021). Therefore, the wolves from India have been identified as unique and qualified as an important population and proposed as Evolutionary Significant Units (ESUs) due to their distinct evolution and adaptation (Hennelly et al., 2021).