The Ambystoma opacum, or marbled salamander, is a fascinating amphibian native to North America. It is distinguished by its modest size, typically between 9 and 11 cm, and its unique black and white coloration, giving it a marbled appearance. This salamander prefers humid habitats such as deciduous forests and marshy areas. It is nocturnal, meaning it is primarily active at night. The marbled salamander is oviparous, laying its eggs in moist depressions before the autumn rains. It is known for its ability to hide under leaves and debris to avoid predators. Although its conservation status is concerning, it is not currently endangered.

The Alpine salamander is a terrestrial amphibian of the Alpine arc, with a shiny black body and short limbs. It inhabits humid montane forests and alpine meadows above 700 m, feeding on insects and small invertebrates. During the breeding season, males and females meet on damp ground to mate, without returning to water.

The tiger salamander is a robust terrestrial amphibian of 15–25 cm (sans la queue), with an olive to brown body marked by yellow blotches and a pale throat. A nocturnal and crepuscular species inhabiting woodlands, damp meadows and pond margins, it feeds on insects, worms and molluscs. During breeding, males produce low underwater calls to attract females to egg-laying sites.

The California tiger salamander is a stout-bodied salamander 15–20 cm long, with a black dorsum marked by yellow or cream spots. Endemic to grasslands, agricultural lands and open woodlands of central and coastal California, it depends on fishless temporary ponds to breed, migrating nocturnally from upland burrows. Adults shelter in rodent burrows during dry periods.

The Seychelles Swiftlet, or Collocalia elaphra, is a small bird endemic to the Seychelles islands. This member of the Apodidae family is characterized by its brownish-grey plumage and its ability to fly swiftly and agilely. It primarily feeds on insects caught in flight. Seychelles Swiftlets often nest in caves or cliffs, using their saliva to build nests. Their population is relatively stable, though confined to their insular habitat. These birds are particularly active during the day, often flying in groups. Their behavior is generally suspicious, making observation challenging for amateur ornithologists.

The sambar, or Cervus unicolor, is a large deer native to South and Southeast Asia. It is recognizable by its dark brown coat and impressive antlers in males. Sambars primarily inhabit dense forests, grasslands, and swamps, feeding on leaves, fruits, and bark. They are generally solitary or live in small family groups. The sambar is a crepuscular animal, active mainly at dawn and dusk. Although hunted for its meat and antlers, it remains relatively widespread in its natural habitat. However, deforestation and overhunting threaten some local populations.

The Sus scrofa moupinensis, commonly known as the Tibetan wild boar, is a subspecies of wild boar found primarily in the mountainous regions of Central Asia. It is distinguished by its robustness and ability to adapt to various environments, ranging from dense forests to alpine meadows. Its coat is generally thicker and darker than that of other subspecies, allowing it to better withstand cold temperatures. Males have prominent tusks, which they use for defense and for digging in the ground in search of food. As an omnivore, its diet is varied and includes roots, tubers, fruits, and small animals.

The Atelopus varius, commonly known as the variable harlequin toad, is a brightly colored toad species native to the tropical rainforests of Central America, primarily in Costa Rica and Panama. This toad is renowned for its vivid colors and distinctive patterns, which vary significantly from one individual to another. Colors can range from bright yellow to green, with contrasting black spots. Unfortunately, this species is critically endangered, mainly due to habitat loss, fungal diseases, and climate change. Conservation efforts are underway to protect this unique amphibian and its natural habitat.

The Ocellated Skink, or Chalcides ocellatus, is a medium-sized lizard, typically measuring between 15 and 20 cm in length. Its skin is smooth and shiny, adorned with characteristic ocellated patterns, from which it derives its name. These patterns, often brownish with lighter spots, allow it to blend effectively into its natural environment. It is primarily found in Mediterranean regions, favoring dry and rocky habitats. Although mainly terrestrial, it can climb small surfaces. The Ocellated Skink is a diurnal animal, active mainly during the hottest hours of the day. It feeds primarily on insects and small invertebrates.

The European serin is a small passerine bird found primarily in gardens, orchards, and urban areas across Europe and the Middle East. It is distinguished by its bright yellow plumage, dark wings, and small size. This small bird primarily feeds on seeds, which it finds in trees, bushes, and grasses. It is also known for its high-pitched, melodious song, which it performs during the breeding season.

The Northern Bat, Eptesicus nilssonii, is a medium-sized bat found in northern Europe and Asia. It is characterized by its dark brown fur, which is often lighter on the belly, and relatively short ears. It primarily inhabits coniferous forests but can also be found in urban areas, using buildings for roosting. This nocturnal species feeds on insects, which it catches in flight using sophisticated echolocation. It is mainly active during summer nights, while it hibernates in winter in caves or abandoned buildings. Although its conservation status is currently considered "least concern," it remains sensitive to human disturbances and the loss of its natural habitat.

The Crotalus atrox, commonly known as the Western Diamondback Rattlesnake, is a venomous snake found primarily in the southwestern United States and northern Mexico. It is easily recognizable by its diamond-shaped pattern on its back and its famous rattling sound, produced by the keratin segments at the end of its tail. This snake can reach a length of 1.5 to 2 meters. It prefers arid habitats such as deserts, grasslands, and sparse forests. Although venomous, it generally only attacks if it feels threatened. Its venom is hemotoxic, affecting blood and tissues, but bites are rarely fatal due to modern treatments.

The Eastern Diamondback Rattlesnake, Crotalus adamanteus, is the largest rattlesnake species in North America, reaching lengths of up to 2.4 meters. It is easily identified by its distinctive diamond-shaped patterns along its back. This venomous snake primarily inhabits pine forests, marshes, and coastal prairies in the southeastern United States. Although feared for its potentially deadly bite, it is generally reclusive and avoids human encounters. Its coloration provides excellent camouflage in its natural habitat. The Eastern Diamondback plays a crucial role in the ecosystem by controlling small mammal populations.

The annulated sea snake is a highly venomous marine elapid, 1–1.5 m long, identifiable by its black and yellow rings covering its slender, elongated body. It inhabits coral reefs, tropical seagrass beds, and shallow lagoons of the Indo-Pacific, feeding on fish and small bony fishes. Solitary and elusive, it employs sinuous undulations and visual cues to hunt.

The Pituophis catenifer, commonly known as the gopher snake, is a non-venomous snake found primarily in North America. It is recognizable by its robust body and distinctive patterns of brown and black spots on a yellow or cream background. Typically measuring between 90 and 180 cm, it can sometimes reach up to 275 cm. This snake is often mistaken for a rattlesnake due to its defensive behavior, which includes hissing and tail rattling. It inhabits various environments, from grasslands to sparse forests, and plays a crucial role in controlling rodent populations. Although it may seem intimidating, it is harmless to humans and contributes to ecological balance.

Elaphe obsoleta, commonly known as the black rat snake, is a non-venomous snake native to North America. It is often found in forests, fields, and rocky areas. This snake is known for its ability to climb trees and swim. Its color ranges from black to dark brown, with a lighter belly. It can reach a length of 1.2 to 2.4 meters. It plays a crucial role in controlling rodent populations. Although it may appear intimidating due to its size, it is generally harmless to humans and prefers to flee rather than defend itself.

The Lampropeltis getula, commonly known as the common kingsnake, is a non-venomous snake native to North America. It is renowned for its ability to resist the venom of other snakes, allowing it to hunt and consume them. This snake exhibits a varied coloration, often black with white or yellow bands. It can reach a length of 1.2 to 1.8 meters. The kingsnake is an opportunistic predator that feeds on rodents, birds, lizards, and other snakes. It is generally active at night and prefers habitats such as forests, grasslands, and rocky areas. Although often captured for the pet trade, it remains abundant in the wild.

The Lampropeltis triangulum, commonly known as the milk snake, is a non-venomous snake from the Colubridae family. It is famous for its colorful patterns that mimic those of venomous coral snakes, a classic example of Batesian mimicry. This snake is generally medium-sized, measuring between 60 and 120 cm in length. Its coloration varies depending on the subspecies, but it often features red, black, and white or yellow bands. It inhabits a variety of environments, from forests to grasslands, and primarily feeds on small mammals, birds, and other reptiles. Nocturnal by nature, it is mostly active at night and rests during the day.

The Saffron Finch, or Sicalis flaveola, is a small bird with a striking bright yellow plumage, accented with olive-green shades on its wings and back. Native to South America, it is often found in savannas, agricultural areas, and urban gardens. This passerine is known for its melodious song and adaptability to various environments. Males display more vibrant colors than females, making them easily identifiable. Their diet mainly consists of seeds, but they also consume insects. The Saffron Finch is a sociable bird, often seen in small groups, especially outside the breeding season.

The Callaeas wilsoni, commonly known as the North Island Kōkako, is an endemic bird of New Zealand. It is easily recognizable by its bluish-grey plumage and bright blue facial wattles. This forest bird is known for its melodious and complex song, often compared to a flute. It primarily inhabits the wet and dense forests of the North Island, where it feeds on fruits, insects, and leaves. Although its flight is weak, it is an excellent climber, using its strong legs to move between branches. Unfortunately, the North Island Kōkako is threatened by habitat loss and predation by introduced species, leading to a significant decline in its population.

The Saimiri sciureus, or common squirrel monkey, is a small arboreal primate native to South America. It is characterized by its dense, soft fur, primarily gray-olive with shades of yellow and white. Its head features a white facial mask contrasting with a black crown. This monkey is highly agile and spends most of its time in the canopy of tropical forests, feeding mainly on fruits, insects, and small vertebrates. Social groups typically consist of 20 to 50 individuals, allowing them to effectively protect against predators. Although they are primarily active during the day, they can sometimes be observed at dusk.

The Alouatta palliata, commonly known as the mantled howler, is an arboreal primate primarily found in the tropical forests of Central and South America. Recognizable by its powerful howl that can be heard for miles, it plays a crucial role in seed dispersal, aiding forest regeneration. This monkey has a black coat with a distinctive golden mane. It lives in hierarchical social groups composed of several males and females. Howler monkeys are primarily herbivorous, feeding on leaves, fruits, and flowers. Their vocal behavior is essential for intra-group communication and territorial defense. Although their population is stable, deforestation poses a threat to their natural habitat.

The patas monkey, or Erythrocebus patas, is an African primate known for its exceptional speed, reaching up to 55 km/h, making it the fastest monkey in the world. It has distinctive reddish fur, a black face, and long, slender limbs adapted for running. Males are significantly larger than females. They primarily inhabit the savannas and semi-arid regions of West and East Africa. Their diet is omnivorous, consisting of fruits, seeds, insects, and small animals. Patas monkeys are diurnal and spend most of their time on the ground, although they can climb trees to feed or rest.

The Tibetan macaque, or Macaca thibetana, is a robust and imposing primate native to the mountainous forests of China. It is distinguished by its thick fur, ranging from golden brown to gray, and its bare, pinkish face. Males are significantly larger than females, sometimes reaching 13 kg. These macaques live in complex social groups led by a dominant male. They are omnivorous, feeding on fruits, leaves, insects, and occasionally small animals. Their habitat is generally between 800 and 2500 meters in altitude, where they adapt to climatic variations. Although their population is stable, deforestation and hunting pose potential threats.

The Callicebus personatus, commonly known as the masked titi monkey, is a medium-sized primate native to the tropical forests of southeastern Brazil. It is characterized by its dark face surrounded by dense, silky brownish fur. These monkeys live in small family groups and are known for their strong social bonds, often seen grooming each other. They primarily feed on fruits, but their diet also includes leaves and insects. Their natural habitat is threatened by deforestation, leading to a decline in their population. Despite this, they sometimes adapt to fragmented forest areas.

The white-bellied spider monkey, Ateles belzebuth, is an arboreal primate primarily inhabiting the tropical forests of South America. Recognizable by its black fur and distinctive white face, it has long limbs and a prehensile tail that enable agile movement through the canopy. This social monkey lives in groups of up to 30 individuals, although they often split into smaller subgroups to forage. Primarily frugivorous, it also consumes leaves, flowers, and insects. Unfortunately, Ateles belzebuth is threatened by deforestation and hunting, leading to a decline in its population.

Chlorocebus pygerythrus, commonly known as the vervet monkey, is a medium-sized primate found primarily in sub-Saharan Africa. It is characterized by its grey-green fur, black face surrounded by white hair, and long, slender tail. These monkeys are highly adaptable and can inhabit a variety of environments, from savannas to riverine forests. They are known for their intelligence and ability to adapt to urban settings. Vervets live in complex social groups where hierarchy and communication play a crucial role. They are diurnal, spending most of the day foraging for food, which mainly consists of fruits, leaves, and insects.

The sitatunga, or Tragelaphus spekii, is a semi-aquatic antelope found mainly in the marshes and wetlands of Central and East Africa. It is easily recognizable by its reddish-brown coat, vertical white stripes, and long spiraled horns in males. Sitatungas are well adapted to their aquatic habitat, with long, splayed hooves that allow them to move easily through swamps. They are primarily active at dawn and dusk, feeding on aquatic plants, grasses, and leaves. Sitatungas are shy and elusive animals, preferring to remain hidden in dense vegetation to avoid predators.

The pygmy nuthatch (Sitta pygmaea) is a small forest passerine, measuring 9–11 cm in length and weighing 8–12 g, identified by its slate-blue dorsal plumage, brighter blue crown, and contrasting white throat. Endemic to western North America’s ponderosa and Jeffrey pine forests, it forages for insects, seeds, and resin in bark crevices. Highly social, it forms stable family groups year-round and often clings upside-down on trunks and branches. The breeding season runs from 01.04–30.06; it nests in cavities, laying 5–9 eggs incubated for 14–17 days, with hatchlings emerging between 15.04 and 17.07.

The Eurasian nuthatch is a small woodland bird found primarily in mixed and deciduous forests across Europe and Asia. It is easily recognized by its blue-grey and orange plumage, light belly, and distinctive black mask around its eyes. This bird is particularly known for its ability to climb upside down on tree trunks, allowing it to reach areas inaccessible to other birds. It primarily feeds on insects, seeds, and nuts.