Отправлено: 06.08.22 20:05. Заголовок: Fauna of Islands of the Indian Ocean

Starting a new topic because this doesn't fit the already existing ones about islands (Atlantic and Pacific).
I saw in the map of the Neocene that Adaman and Nicobar still exist, so I thought about some species that could exist here. Since it was a chain of islands, I think that the fauna could be different in each of them. For example, the largest one (Adaman itself) could have maintained large introduced species such as the chital deer and feral dogs. These animals would have descendants in the Neocene.
Meanwhile in Great Nicobar, terrestrial predators could be absent and the largest animal could be a flightless descendant of the Nicobar pigeon .
What do you think?

 Отправлено: 06.08.22 22:02. Заголовок: JOrnitho пишет: lar..

JOrnitho пишет:

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large introduced species

We can certainly say, their descendants will be dwarf.
JOrnitho пишет:

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a flightless descendant of the Nicobar pigeon

This species is classified now as near threatened. So, it is more probable that a descendant of any continental species will do it... in conditions of absence of rats and mice.

 Отправлено: 07.08.22 11:45. Заголовок: JOrnitho Another to..

JOrnitho
Another topic - our English part of the forum keeps expanding! Thanks!

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a flightless descendant of the Nicobar pigeon

Would be great, but the Author mentioned above that it would hardly survive because of being already threatened in holocene. So, we have to use another ancestor. Which can also become colorful, not necessarily dull grey. Or even crested, like crowned pigeons.

 Отправлено: 07.08.22 11:59. Заголовок: In this case, I thin..

In this case, I think that the ancestor of a flightless bird in Nicobar could be the domestic chicken left behind by the men. Being already terrestrial, it could have grow to a large size.

 Отправлено: 07.08.22 12:09. Заголовок: JOrnitho Nice idea!..

JOrnitho
Nice idea! Like the megapode, but flightless.

 Отправлено: 07.08.22 15:25. Заголовок: Биолог пишет: Nice ..

Биолог пишет:

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Nice idea! Like the megapode, but flightless.

Yes! Perhaps even like the extinct Sylviornis with the exception that they will incubate their eggs. These birds could have strong legs to use in intraspecific fights.
Meanwhile in Andaman Island, there would be a dwarf descendant of the chital deer being hunted by the top predator of the place, a canid.

 Отправлено: 07.08.22 19:06. Заголовок: JOrnitho Sylviornis..

JOrnitho

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Sylviornis

Wow, you've introduced me to an extinct species I never knew about before! Good idea.

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in Andaman Island, there would be a dwarf descendant of the chital deer being hunted by the top predator of the place, a canid

Chital deer was introduced on Andaman in the XX century, as can be found in Internet. A descendant there is a good idea! Chital deer is beautiful, so the descendant can inherit that.

 Отправлено: 08.08.22 03:39. Заголовок: Биолог пишет: Wow, ..

Биолог пишет:

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Wow, you introduced to an extinct species I never knew about before! Good idea.

The Sylviornis is a very interesting animal. It shows how the evolution in islands can generate strange animals. Perhaps in the Neocene these islands could have animals with different and even bizarre forms.

 Отправлено: 08.08.22 11:40. Заголовок: JOrnitho OK, so be ..

JOrnitho
OK, so be it!

 Отправлено: 08.08.22 13:38. Заголовок: Finished the descrip..

Finished the description of the giant descendant of the domestic chicken. I'll finish the one for the dwarf deer of Andaman later today.

Emperor junglefowl (Gigantogallus imperator)
Order: Galliformes
Family: Phasianidae
Habitat: Forests and woodlands of Nicobar Island
During the Holocene, the man introduced many species to other continents. Some only because of their ornamental value, while others were introduced because they were useful for agriculture. Among the birds, the domestic chicken (Gallus domesticus) was the species that reached more continents. With the disappearance of humanity, they were left behind to fend for themselves. Some were successful in surviving and continued to evolve. In the Neocene, the chickens that were left in Nicobar Island had evolved into a large flightless species, the Emperor junglefowl. Such characteristic was only possible due to the disappearance of terrestrial predators in the island.

The emperor junglefowl is the largest animal of Nicobar Island. A completely adult male can reach 175 cm of height, surpassing their relative of the Genus Aepygallus from Mauritius. The female has a more modest size, 147 cm.  These birds are also heavy, with the male having 32 kg while the female has 23 kg. To sustain such weight, their bones had evolved to be denser, like that of an ostrich. They have a large skull with a high and laterally compressed orange beak. Its yellow colored legs are rather short, but have strong toes with long nails. Most of their height comes from their long necks. The wings are reduced, making it impossible for them to fly.

Beyond the size, the only other difference between the sexes is that the males have a bare face with red skin that forms a comb and wattles. These bare parts become bright during the nesting season. The comb is large, reaching 20 cm in older males. The wattles are long and come down from both sides of their head, below the auricular hole. This gives the bird the appearance of having earlobes. The female lacks such structures and the skin on their face is pale pink. Both sexes have the same dark brown plumage, with yellowish-brown underparts. The tails are short, being metallic green in the males and brown in the females.

The emperor junglefowl is omnivorous. It'll feed on arthropods, terrestrial gastropods, seeds, fruits and leaves. They use their long legs to reach fruits and leaves in tree branches. These birds will also visit beaches in search of algae and shellfish, which is excavated out of the sand. Their shell is crushed by the birds' strong beak.

This species lives in harens formed by a dominant male and two to four females. Their nesting season starts during the end of the dry season. The females will make nests in the territory of the group, usually hidden among bushes and below trees, near its roots. Usually three to six reddish-brown eggs are laid, which are incubated solely by the female for 30 days. The male will stay patrolling his territory in search of possible rivals and invasor, which will be expelled with kicks of their strong legs. After hatching, the chicks are already capable of leaving the nest. They will follow the mother back to the group and if other females already have chicks, a crèche is formed by them. The young reach full adult size in about six months. At this point, the male chicks are expelled by their father. The females can remain indefinitely, but they leave as soon as sexual maturity is reached with two years of age. At this point, they will leave, with some even traveling in small female-only groups in search of a male to form their own harem. The lifespan of this species is 15 years.

 Отправлено: 08.08.22 21:11. Заголовок: JOrnitho Great spec..

JOrnitho
Great species!

 Отправлено: 09.08.22 04:59. Заголовок: Биолог пишет: Great..

Биолог пишет:

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Great species!

Thanks! I finished the description of the dwarf deer of Andaman Island.

Dwarf chital (Nanoaxis maculatus)
Order: Artiodactyla
Family: Cervidae
Habitat: Forests and woodlands of Andaman Island
During the Holocene, humans had caused several impacts on the environment. Among their actions was the introduction of exotic species. The chital deer (Axis axis) was introduced by the humans in the Andaman Island, becoming a very successful species here. Such success allowed them to survive in the Neocene, with its descendant now living here. The dwarf chital is such a descendant. This small cervid is a common species across the forests and woodlands of the Island.
The dwarf chital has 50 cm of shoulder height and 110 cm of length. The male has a pair of 15 cm long antlers that have only one short branch in its middle. The fur of both male and female in the upperparts are rufous and completely covered in white patches. The abdomen, rump, throat, insides of legs, ears, and most of the tail are all light brown. The tail, 20 cm long, has a dark tip.
They feed on a wide variety of vegetation, including grasses, foliage, browse, fruit, and water plants, depending on the local habitat.
This deer is active throughout the day. In the summer, time is spent resting under shade. As days grow cooler, foraging begins before sunrise and peaks by early morning. Activity slows down during midday, when the animals rest or loiter about slowly. Foraging recommences by late afternoon and continues till midnight. They fall asleep a few hours before sunrise, typically in the forest. When cautiously inspecting its vicinity, the dwarf chital stands motionless and listens with rapt attention, facing the potential danger, if any. This stance may be adopted by nearby individuals, as well. As an antipredator measure, the deer flee in groups, sprinting often and hiding in dense undergrowth. The running dwarf chital has its tail raised, exposing the black tip.
A gregarious animal, the dwarf chital forms matriarchal herds comprising an adult female and her offspring of the previous and the present year. For most of the year, adult males and females are segregated into different herds. Female herds are larger while bulls form small groups and may even travel alone. Young bulls may associate with older bulls or close related female groups. Male and female herds come together only during the mating season, which starts during the middle of autumn. Herd membership is typically that of 15 to 30 individuals, aggregations of as many as 100 individuals can happen.
A vocal animal, this deer gives out bellows and alarm barks. Bellowing coincides with rutting, which starts during the middle of the middle of the dry season. Dominant males guarding females in oestrus make high-pitched growls at less powerful males. Males may moan during aggressive displays or while resting. Dwarf chitals, mainly females and juveniles, bark persistently when alarmed or if they encounter a predator. Fawns in search of their mother often squeal. The chital can respond to the alarm calls of several animals
The gestation period of the dwarf chital is of 6 months and they usually bear one offspring at a time, but sometimes produce twins. Females usually give birth in dense growth so that they are hidden from the rest of the herd and predators. Weaning is completed at around 7 months and at around 12 months the fawn is independent, the young males remain in its mother herd until reaching one year. After that, they will walk away from the herd, but can return to it occasionally. Adult males often fight between one another for the chance of mating of females, using kicks and bites more than their antlers. Reaching sexual maturity with 3 years, the dwarf chital have a lifespan of 17 years.

 Отправлено: 09.08.22 09:33. Заголовок: Why do not they have..

Why do not they have white rump patches like their ancestors? It would be a more visible warning in forests.

 Отправлено: 09.08.22 11:12. Заголовок: медведь The white p..

медведь
The white patches can be a way of disguise in the foliage, not warning.

 Отправлено: 09.08.22 15:05. Заголовок: медведь пишет: Why ..

медведь пишет:

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Why do not they have white rump patches like their ancestors? It would be a more visible warning in forests.

The white patches are located in their upperparts, like their ancestors. They are larger than the spots of the chitals of the Holocene. I believe that for warning, the black tip in the tail would be better. The white patches are camouflage, like how Биолог said.

 Отправлено: 09.08.22 11:13. Заголовок: JOrnitho Good deer!..

JOrnitho
Good deer!

 Отправлено: 10.08.22 05:17. Заголовок: I finished the descr..

I finished the description of the predatory canid of the Andaman Island.

Strong-jawed dog (Ferociocanis borophagus)
Order: Carnivora
Family: Canidae
Habitat: Forests and woodlands of Andaman Island
During the Holocene, humans had caused several impacts on the environment. Among their actions was the introduction of exotic species. Being a common companion, the dog was among the animals that were spread by the humans across several continents. With humanity’s disappearance, these mammals stayed behind. The survivors left several descendants during the Neocene. In the Andaman Island, the dog gave rise to the strong-jawed dog. 
The strong-jawed dog is the largest predator of the Island. However, if compared to continental predators, they are small. An adult has 40 cm of height at the shoulders and 89 cm of body length. Their fur is short, being dark brown in the upperparts and reddish-brown in the underparts. Their tail have short fur and have a white tip. This species has strong muscles in the skull and powerful teeth and jaws. Such characteristics allow them to crush bones.
They are carnivores, feeding on any large vertebrate that inhabits Andaman Island. Their main prey is the dwarf chital. While the strong-jawed dogs have a small size, they compensate for it with their powerful bite that allows the canids to kill their prey more easily. They will occasionally visit beaches in search of marine animals that ended up there and died.
Differently from wolves from the Holocene, this canid hunts in pairs and doesn't form packs. The strong-jawed dog is monogamous, with them being more common to be seen in pairs. They are sometimes accompanied by their most recent litter of pups. Scent marking through urination and defecation is common around strong-jawed dog den areas and on the trails they most often use. Scent marking is used to assist in territorial defense. The females have only one breeding cycle each year. They excavate dens, with the breeding pairs being spaced well apart and maintaining a core territory around their dens. Breeding occurs during the end of the dry season, with the mating period lasting up to 29 days. Gestation lasts 72 days, and the timing of the births coincides with the annual abundance of food, usually the beginning of the monsoon. The female gives birth to 3-5 pups. The pups are born with closed eyes that open after 13 days, with the ears erecting after 12 days. Their teeth erupt at 16 days after birth, and the eruption of adult dentition is completed after five months. Pups are born with soft fur that ranges in color from light gray to dark brown. At the age of one month, their fur is shed and replaced with one similar to that of an adult.  Lactation lasts for up to 9 weeks and the pups begin to eat meat at the age of 19 days. After three weeks that the lactation is concluded, the parents expel the pups from their territory. Females reach sexual maturity after 11 months, while males at 22 months. They have a lifespan of 17 years.

 Отправлено: 10.08.22 09:19. Заголовок: JOrnitho Good dog!..

JOrnitho
Good dog!

 Отправлено: 22.08.22 13:43. Заголовок: I was thinking about..

I was thinking about some other animals for the Andaman and Nicobar Islands. One would be a descendant of the wild pig similar to a elephant, but with the size of a tapir. Other idea would be a large bird if prey that hunt the giant junglefowl. It could also live in nearby areas of the continent. What other species do you think that could also live here? Maybe some of the continent that reached it after the humans disappeared?

 Отправлено: 22.08.22 15:46. Заголовок: JOrnitho a descenda..

JOrnitho

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a descendant of the wild pig similar to a elephant, but with the size of a tapir

OK, normal. Although tapirs are not much larger than wild boars.

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Other idea would be a large bird if prey that hunt the giant junglefowl.

Resembling the Haast eagle? Well, the islands seem too small for a so large predatory bird, but OK.

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What other species do you think that could also live here? Maybe some of the continent that reached it after the humans disappeared?

Possible, but only for small birds, the size of a sparrow or finch. Although they could become larger after settling on the islands.

 Отправлено: 22.08.22 21:28. Заголовок: Биолог пишет: Resem..

Биолог пишет:

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Resembling the Haast eagle? Well, the islands seem too small for a so large predatory bird, but OK.

I think that would be smaller, maybe with the size of harpy or golden eagle. It would kill the junglefowl by coliding against its neck with full force and using the claws

Биолог пишет:

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Possible, but only for small birds, the size of a sparrow or finch. Although they could become larger after settling on the islands

This is interesting. A finch could fill the niche of parrots and other species that don’t exist in the islands.

 Отправлено: 23.08.22 11:37. Заголовок: JOrnitho I think th..

JOrnitho

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I think that would be smaller, maybe with the size of harpy or golden eagle. It would kill the junglefowl by coliding against its neck with full force and using the claws

OK, sounds good!

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A finch could fill the niche of parrots and other species that don’t exist in the islands.

Yes, why not. I thought it could become as large as a common pigeon.

 Отправлено: 23.08.22 13:47. Заголовок: Биолог пишет: I th..

Биолог пишет:

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I thought it could become as large as a common pigeon.

I like this idea. They could be descendants of the munia that came from Indian subcontinent. Other niches that they could fill is that of nectarivores and insectivores. They could develop specialized beaks for that too.

 Отправлено: 23.08.22 16:45. Заголовок: JOrnitho Yes, sound..

JOrnitho
Yes, sounds good, except for niches. Munias feed primarily on seeds and have thick strong beaks adapted to this. So, switching to insects and nectar would involve tremendous changes in the beak structure.

 Отправлено: 23.08.22 21:53. Заголовок: Биолог пишет: So, s..

Биолог пишет:

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So, switching to insects and nectar would involve tremendous changes in the beak structure.

Yes. I was thinking how the Hawaiian honeycreepers are descendants of cardueline finches. They also developed different beaks. Maybe something similar could happen in these islands.

 Отправлено: 24.08.22 11:14. Заголовок: JOrnitho Oh, I didn..

JOrnitho
Oh, I didn't know that honeycreepers were descendants of carduelines. OK, so be it.

 Отправлено: 24.08.22 22:46. Заголовок: So, for the insectiv..

So, for the insectivores descendants, I was thinking that they could be adapted to feed by gleaning, similar to the genus Anabacerthia from South America. Meanwhile, the nectarivores could be similar to the Dacnis from South America.

 Отправлено: 25.08.22 09:56. Заголовок: JOrnitho OK, so be ..

JOrnitho
OK, so be it.

 Отправлено: 01.09.22 13:21. Заголовок: Do you have suggesti..

Do you have suggestions for the ancestor of the eagle-like bird of prey that could inhabit the Andaman and Nicobar Islands?

 Отправлено: 01.09.22 15:53. Заголовок: JOrnitho Unfortunat..

JOrnitho
Unfortunately no. Perhaps some species of Indian hawk...

 Отправлено: 01.09.22 21:31. Заголовок: Биолог пишет: Perha..

Биолог пишет:

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Perhaps some species of Indian hawk...

Maybe the shikra (Accipiter badius)? It's relatively common in India nowadays.

 Отправлено: 02.09.22 07:45. Заголовок: JOrnitho Yes, why n..

JOrnitho
Yes, why not.

 Отправлено: 21.01.23 01:37. Заголовок: I read in article th..

I read in article that the northern palm squirrel (Funambulus pennantii) was introduced in Andamans Islands. It gave me an idea for a descendant of this species that developed the ability of gliding between trees. It would be a case of convergent evolution with the true flying squirrels. What do you think of this?

 Отправлено: 21.01.23 11:43. Заголовок: JOrnitho Good idea...

JOrnitho
Good idea.

 Отправлено: 21.01.23 10:17. Заголовок: It can be, good idea..

It can be, good idea.

 Отправлено: 21.01.23 15:15. Заголовок: In addition to that,..

In addition to that, I thought that they could have spread to the other islands of the Archipelago through rafting. In each island, a different sized species developed, with the largest one living in great Andaman.

 Отправлено: 21.01.23 17:46. Заголовок: JOrnitho Hmm, do yo..

JOrnitho
Hmm, do you expect them to belong to the same genus?

 Отправлено: 21.01.23 18:28. Заголовок: Биолог пишет: do yo..

Биолог пишет:

цитата:

do you expect them to belong to the same genus?

I'm not sure. I think that the smaller ones would be from another genus.

 Отправлено: 22.01.23 10:43. Заголовок: JOrnitho OK...

JOrnitho
OK.

 Отправлено: 22.01.23 16:41. Заголовок: Other species that c..

Other species that could live in these islands is a nocturnal descendant of black rats that feed in descendants of cocconuts. I have an idea for these plants too. Given the way that they spread, I think the fruits could also be found in the continent.

 Отправлено: 22.01.23 20:46. Заголовок: JOrnitho Well, look..

JOrnitho
Well, looks plausible. But do you expect the rats to eat the entire contents of coconuts? If this is a common action, the coconut palm would not survive for long, having limited numbers of nuts eaten by rats before they germinate into new trees.

 Отправлено: 22.01.23 23:27. Заголовок: Биолог пишет: But d..

Биолог пишет:

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But do you expect the rats to eat the entire contents of coconuts? If this is a common action, the coconut palm would not survive for long, having limited numbers of nuts eaten by rats before they germinate into new trees.

What parts of the coconut you think that they could eat without destroying the chances of germination? Perhaps the fruits would only be a part of their diet?

 Отправлено: 23.01.23 14:19. Заголовок: JOrnitho I think th..

JOrnitho
I think the rats would eat something else. And in the cocnuts, they would eat only the soft parts around the seed. Also, given the hardness and toughness of the coconut shell, the rats would have to acquire adamantium-like incisors

 Отправлено: 23.01.23 19:02. Заголовок: Биолог пишет: Also,..

Биолог пишет:

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Also, given the hardness and toughness of the coconut shell, the rats would have to acquire adamantium-like incisors

Well, some species of rat really eat the coconuts, being considered plagues for the production of that fruit. What if the coconut of Andaman and Nicobar developed a strategy? Perhaps a thick, soft and sweet part around the true seed, which is sour and not palatable for the rodents?

 Отправлено: 23.01.23 22:58. Заголовок: JOrnitho some speci..

JOrnitho

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some species of rat really eat the coconuts, being considered plagues for the production of that fruit.

I did not know that, my fault.

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What if the coconut of Andaman and Nicobar developed a strategy? Perhaps a thick, soft and sweet part around the true seed, which is sour and not palatable for the rodents?

Wow, great! But the seeds would obviously require protection from sour juice as they germinate through it (in palms, the seeds do not fall out before germination). Another way is to develop a toxin, and another one is a sharp, repulsive smell (like durian has it, but not necessarily putrefactive) that would drive the rats off without harming the seeds inside.

 Отправлено: 24.01.23 04:03. Заголовок: Биолог пишет: Anoth..

Биолог пишет:

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Another way is to develop a toxin, and another one is a sharp, repulsive smell (like durian has it, but not necessarily putrefactive) that would drive the rats off without harming the seeds inside.

Perhaps the coconut could have its external portion being sweet and soft, but the seed itself have a terrible smell? The rats would this part, but leave the rest behind. By doing it they help the plant germinate.

 Отправлено: 24.01.23 11:38. Заголовок: JOrnitho Yes, why n..

JOrnitho
Yes, why not.

 Отправлено: 24.01.23 12:02. Заголовок: JOrnitho If you'..

JOrnitho
If you'll release this gliding rodents and interesting coconuts I'll back to making chapter about them, but it isn't 100% unformation.

 Отправлено: 28.01.23 15:09. Заголовок: I'll start to wo..

I'll start to work in the description for these rodents today, this week had been so busy. Someone could help me with the coconut? Botanic isn’t my area of expertise.

 Отправлено: 28.01.23 19:19. Заголовок: JOrnitho What kind ..

JOrnitho
What kind of help do you need?

 Отправлено: 29.01.23 12:18. Заголовок: Биолог пишет: What ..

Биолог пишет:

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What kind of help do you need?

To describe the soft layer that cover the seed and is consumed by the rats. I thought that it could have appeared as way to protect the fruit from the elements, but to germinate is necessary to be removed. Also, these coconuts would be smaller than their ancestors.

 Отправлено: 29.01.23 12:49. Заголовок: JOrnitho But the co..

JOrnitho
But the coconuts have a thick and tough shell that is a great protection from elements, isn't it? So this shell will become much thinner and/or softer. Also, note that the palm coconuts are adapted to floating from island to island across the ocean water, the seeds being protected from the salty water by the shell, and the soft tissue inside providing buoyancy. Will this stop in the case of your idea?

 Отправлено: 29.01.23 20:15. Заголовок: Биолог пишет: But t..

Биолог пишет:

цитата:

But the coconuts have a thick and tough shell that is a great protection from elements, isn't it? So this shell will become much thinner and/or softer. Also, note that the palm coconuts are adapted to floating from island to island across the ocean water, the seeds being protected from the salty water by the shell, and the soft tissue inside providing buoyancy. Will this stop in the case of your idea?

No, they would continue this way. How we could explain biologically the creation of this soft part of the shell? Perhaps a defense against predation? The rats would eat this part, but leaving the interior intact?

 Отправлено: 29.01.23 20:28. Заголовок: JOrnitho OK, so be ..

JOrnitho
Yes, OK, so be it.

 Отправлено: 01.02.23 04:20. Заголовок: Finished the first g..

Finished the first group of squirrels and the description of a bird of prey:

Andaman flying squirrel (Parapteromys versicolor)
Order: Rodentia
Family: Sciuridae
Habitat: Forests of Andaman Island, tree canopy
During their expansion, the humans had introduced several species. The northern palm squirrel (Funambulus pennantii) was left by them on the Andaman Islands, where they survived to the transition between the Holocene and Neocene. In a case of evolutionary convergence to other rodents, their descendants had developed large membranes (or patagia) that span the space between the fore- and hindlimbs, and additional membranes connect the trailing edges of the hindlimbs with the proximal parts of the tail. These insular flying squirrels form the tribe Parapteromyini, which is formed by two genus: Parapteromys and Microparapteromys. Through rafting, they had spread from Andaman to several nearby islands, including Nicobar.

The genus Parapteromys is formed by the giant insular flying squirrels. Its main representative is the andaman flying squirrel. This species is also the largest, with a head-to-body length of 38 cm and a tail of 34 cm. Their underparts are white, while the upperparts are rufous-brown, with a darker midback. The tail is black with a white tip. Their head is pale gray.

They are diurnal animals, with a diet composed mostly of seeds, nuts and fruits. However, they’ll also eat insects, eggs, chicks, smaller mammals and reptiles.

The Andaman flying squirrel is a solitary animal, spending a majority of its life without interaction with others of its own species, with the exception of during mating season and females with young. The gestation period is 34 days, with the breeding taking place in grass nests during the autumn. Litters of two or three are common. The young are weaned after about 10 weeks and are sexually mature at 9 months. This species has a lifespan of 7 years.

Another representative of the genus is the Nicobar flying squirrel (Parapteromys nicobariensis), which is endemic to Great and Little Nicobar. This species is the smallest representative of the genus, with 32 cm of body length and a tail of 24 cm. Their underparts are yellowish-white, while the underparts are reddish-brown. The tail is black. The Malacca flying squirrel (Parapteromys intermedius) inhabits Car Nicobar. This species can be considered the middle term between the other two, with a body length of 34 cm and a tail of 27 cm. Their underparts are white with a yellowish part in the center, while the upperparts are reddish-brown with darker tones in the rear and near the base of the tail. The tail is black with a small white tip.

Indian hawk-eagle (Accipteraetus shikra)
Order: Accipitriformes
Family: Accipitridae
Habitat: Tropical forests from Hindustan to Sunda Land, with incidental occurrence in Nicobar Islands. 
The human actions during the Holocene caused the decline of many species. However the species that were resilient enough survived, with their descendants now living in the Neocene. The shikra (Accipiter badius) had survived in the Indian subcontinent, giving rise to the Indian hawk-eagle. This species inhabits the tropical forests from Hindustan to Sunda Land, with incidental occurrence in Nicobar Islands. 


The Indian hawk-eagle has a body length of 70 cm and wingspan of 185 cm. Like nearly all birds of prey, the females are larger and heavier than the males. Adults have dark brown upperparts, a brown tail with six bars, a white patch in the wings that is visible in flight, white underparts, and a dark gray head with a white crown. 


Their diet consists of birds, lizards, snakes and mammals. The size of their mammalian prey ranges from rodents to monkeys. Individuals of the population living in Nicobar are capable of hunting Emperor junglefowl. Usually, a couple is capable of bringing down these large phasianids by working together. The male will distract the bird, while the female attacks from behind.


Indian hawk-eagles, like most but not all raptors, live solitarily or in pairs. Breeding territories are maintained through high circling, either by a solo adult or by a pair. Most displays occur in mid to late morning and are usually at fairly low heights with occasional calling. The breeding season starts in the summer. Nests are placed in relatively exposed branches, often being on the main crutch of the tree or the largest, most bare branch. They are made of twigs and lined with grass. The usual clutch is 2 to 3 eggs  which are pale bluish gray stippled on the broad end in black. The incubation period is 45 days and both parents help with it, but the female is the one that incubates for the longest time.


Like all birds of prey, the hatchlings are initially altricial. In this species, the chicks are still unable to lift their heads at 3 days old. By about two weeks of age, the young bird can start to stand on its folded leg within the nest. The begging calls will increase at about 3 weeks of age. They fledge within 95 days. At 12 weeks, the full juvenile plumage is attained. Despite the full plumage and powers of flight, the juvenile bird continues to linger in the vicinity of the nest, typically venturing no further than 150 m from the nest for months. The young eagles often continue to beg loudly for food, especially once their parents are in view, but if their crop is full they often retire to quietly sit in dense foliage. They reach sexual maturity with 7 years and have a lifespan of 27 years.

 Отправлено: 01.02.23 10:47. Заголовок: JOrnitho Very good!..

JOrnitho
Very good!

 Отправлено: 01.02.23 13:04. Заголовок: JOrnitho It's g..

JOrnitho
It's good! I like this.

 Отправлено: 01.02.23 18:24. Заголовок: Good translation!..

Good translation!

 Отправлено: 02.02.23 12:03. Заголовок: Thanks, everyone! I..

Thanks, everyone! I finished the description of the second flying squirrel genus. The next will be the rat.

Katchal flying squirrel (Microparapteromys agilis)
Order: Rodentia
Family: Sciuridae
Habitat: Forests of Katchal Island, tree canopy
During their expansion, the humans had introduced several species. The northern palm squirrel (Funambulus pennantii) was left by them on the Andaman Islands, where they survived to the transition between the Holocene and Neocene. In a case of evolutionary convergence to other rodents, their descendants had developed large membranes (or patagia) that span the space between the fore- and hindlimbs, and additional membranes connect the trailing edges of the hindlimbs with the proximal parts of the tail. These insular flying squirrels form the tribe Parapteromyini, which is formed by two genus: Parapteromys and Microparapteromys.

The genus Microparapteromys is formed by the dwarf insular flying squirrels. Differently from the Parapteromys, these small rodents are endemic to islands of the Archipelago of Nicobar. Their main representative is the Katchal flying squirrel, an inhabitant of the forested areas of small Katchal Island. This species is the typical representative of the group, with a head-to-body length of 15 cm and a tail of 12 cm. Their underparts are white, while the upperparts are dark brown. The tail is black and the head is light brown.

They feed mostly on fruit and nuts from trees, but will also eat insects, buds, mushrooms, bird eggs, nestlings, and flowers.

Like all representatives of the genus Microparapteromys, the Katchal flying squirrel is diurnal and solitary. The males and females only meet during the mating season, which happens during autumn. The gestation period is approximately 40 days. Young are born without fur or any capabilities of their own. Their ears open at 2 to 6 days old, and fur grows by 7 days. Their eyes do not open until they are 25 days old. Mothers wean their young 65 days after they are born. The young then become fully independent at around 120 days of age, sexual maturity is reached around this time. They have a lifespan of 4 years.

The genus Microparapteromys have other representatives:

Teressa flying squirrel (Microparapteromys minor) inhabits the forests of Teressa island. This species is the smallest representative of the genus, with a head-to-body length of 13 cm and a tail of 10 cm. Their underparts are whitish-yellow, while the upperparts and head are light brown. The tail is pale gray.

Camorta flying squirrel (Microparapteromys gracilis) inhabits the forests of Camorta island. This species have a head-to-body length of 15 cm and a tail of 11 cm. Their underparts are white, while the upperparts and head are dark brown. The tail is dark gray.

 Отправлено: 02.02.23 12:39. Заголовок: JOrnitho Interestin..

JOrnitho
Interesting animal.

 Отправлено: 02.02.23 14:23. Заголовок: Interesting animal!..

Interesting animal!

 Отправлено: 02.02.23 20:20. Заголовок: JOrnitho Good ones!..

JOrnitho
Good ones!

 Отправлено: 02.02.23 14:29. Заголовок: Yes, really interest..

Yes, really interesting flying squirrels!

 Отправлено: 03.02.23 00:38. Заголовок: Finished the rats: ..

Finished the rats:

Striped coconut rat (Palmaromys striatus)
Order: Rodentia
Family: Muridae
Habitat: Forests of Great Andaman and nearby islands
During their expansion, the humans had inadvertently transported several commensal species with them. The black rat (Rattus rattus) was one of the animals that became widespread thanks to anthropogenic expansion. The populations of Andaman and Nicobar had survived into the Neocene, giving rise to genus Palmaromys, the coconut rats. The main representative of the genus is the striped coconut rat, an inhabitant of Great Andaman and nearby islands.

The striped coconut rat has a head-to-body length of 18 cm and a prehensile tail of 22 cm. Their underparts are white. It has reddish-brown fur on its upper body and two dark brown stripes contrasting with light brown stripes along its back. They have strong incisors and powerful muscles in the head, which allow them to break the thick shell of coconuts and seeds. Another characteristic of the Palmaromys as a genus is that they developed cheeck pouches that are used to carry food back to their dens. It’s usually shared by them.

This species is omnivorous, but they have a preference for coconuts. They also eat soft fruits, seeds, flowers, insects and eggs. The striped coconut rat has an arboreal lifestyle, rarely descending to the ground. When foraging, they can travel several kilometers per night from where their dens are located.

The striped coconut rat is nocturnal and monogamous. The male and female form family groups with their youngest offspring. These groups inhabit the same den, which is usually inside a hollowed tree or rock crevice. The family leave their dens during the dusk and disperse to seek food, usually the parents will remain together. During the entire night, they will vocalize to each other to maintain contact. Some are loud, while others are ultrasonic.

They breed during the entire year, with the female producing up to five litters a year. The gestation period is only 21 days, and litters can number up to 14, although seven is more common. They reach sexual maturity in about five weeks, but the young will remain with their parents until reaching one month. During this period, they help take care of their siblings. A "babysitter" will remain at the den with the young, while the others leave to eat. In these cases, the parents will return with some food for them inside of their cheeck pouches. The lifespan of this species is 2 years.

Another representative of the genus Palmaromys is the Spectacled coconut rat (Palmaromys nicobarensis), an inhabitant of Great Nicobar and nearby islands. This species has a head-to-body length of 15 cm and a prehensile tail of 19 cm. Their underparts are whitish-yellow. It has dark brown fur on its upper body and white markings across its face, which gives them a "spectacled" appearance.

 Отправлено: 03.02.23 09:35. Заголовок: Interesting animal!..

Interesting animal!

 Отправлено: 03.02.23 10:31. Заголовок: JOrnitho Very good ..

JOrnitho
Very good rats! But the name... Maybe, you meant striped, which means "decorated with stripes"? Because "stripped" is a past participle of "to strip" (same as "to undress").

 Отправлено: 03.02.23 11:55. Заголовок: Биолог пишет: Becau..

Биолог пишет:

цитата:

Because "stripped" is a past participle of "to strip" (same as "to undress").

Thanks! I corrected it.
Now only the description of the coconut remains.

 Отправлено: 04.02.23 15:25. Заголовок: Another island that ..

Another island that could have an interesting fauna is Comoros. The mongoose lemur (Eulemur mongoz) was introduced here and live well in the forests. Maybe a descendant of this species could live there in the Neocene?

 Отправлено: 04.02.23 20:45. Заголовок: JOrnitho Why not?..

JOrnitho
Why not?

 Отправлено: 06.02.23 14:08. Заголовок: Besides the descenda..

Besides the descendant of the lemurs, Comoros could have a descendant of pigs with dwarfism and a feline with size of a fossa, which would hunt the pig and the lemurs. Any ideas for more animals?

 Отправлено: 06.02.23 18:45. Заголовок: JOrnitho пишет: Any..

JOrnitho пишет:

цитата:

Any ideas for more animals?

As I know, caecilians also live there. What is their conservation status?

 Отправлено: 06.02.23 22:22. Заголовок: Автор Of which spec..

Автор
Of which species? I like the idea of caecilians, we really lack them in Neocene. And they definitely could survive in their underground burrows.

 Отправлено: 06.02.23 22:56. Заголовок: I'll need to sea..

I'll need to search about the caecilians, but I think that rather than having a predatory cat, it could be a descendant of the Javan mongoose, which was also introduced in Comoros. It could still become a fossa-like animal.

 Отправлено: 07.02.23 10:51. Заголовок: JOrnitho A fossa-li..

JOrnitho
A fossa-like mongoose is interesting.

 Отправлено: 07.02.23 21:02. Заголовок: Another idea that I ..

Another idea that I had is for a most frugivorous descendant of the also introduced small Indian civet (Viverricula indica). Having the appearance of a very small fox, it would also be prey of the fossa-like mongoose.

 Отправлено: 07.02.23 23:08. Заголовок: JOrnitho You mean a..

JOrnitho
You mean a frugivorous animal would become a predator?

 Отправлено: 08.02.23 02:43. Заголовок: Биолог пишет: You m..

Биолог пишет:

цитата:

You mean a frugivorous animal would become a predator?

No, I mean that the small Indian civet (Viverricula indica), an omnivorous species, could have a fox-like descendant that became more frugivorous. This new species of viverrid would be preyed by the fossa-like mongoose.

 Отправлено: 08.02.23 09:00. Заголовок: JOrnitho OK...

JOrnitho
OK.

 Отправлено: 10.02.23 03:58. Заголовок: I'm working in t..

I'm working in the descriptions for the animals of the Comoros Islands, but after reading more I concluded that each island would have their own endemic fauna. They are far away enough to avoid animals swimming between them.

 Отправлено: 10.02.23 12:51. Заголовок: I think that the onl..

I think that the only animals that can spread to other islands are small ones, moving through rafting. This way, I thought that there could be a descendants of the brown rat that evolved to become analogues of the macropodes. They would have large hindfeet and would move by jumping. The largest species would have the size of a small wallaby.

 Отправлено: 11.02.23 04:33. Заголовок: Finished the descrip..

Finished the description of three animals for Comoros Islands, the rest comes later after I finish working on it.

Comoros dwarf hog (Parvosus sociabilis)
Order: Artiodactyla
Family: Suidae
Habitat: Forests and woodlands of Ngazidja Island
During their expansion, the humans had transported several domesticated animals with them. Among them was the domestic pig (Sus domesticus), which was capable of surviving in the Comoros Islands. Their descendant is the Comoros dwarf hog, a small and highly gregarious omnivore that inhabits Ngazidja, the largest island of the archipelago.

The Comoros dwarf hog is one of the smallest Suids of the Neocene, with an adult having 28 cm of height and 72 cm of length. They have a striking reddish-brown fur, with black legs and a tufted dark brown stripe along the spine. They have several white mottles around their fur. Besides being slightly larger than females, the males have the upper canines visible on the sides of their mouths.

This species is diurnal and forage for food during the daylight hours. Foraging usually takes place for about 10 hours a day, with the hog generally taking a break midday in order to escape the high heat of the afternoon. Dwarf hogs are also omnivorous and feed primarily on roots, tubers, fallen fruits and other vegetative food, as well as on insects, rodents, eggs, young birds, and small reptiles.

The dwarf hogs are social animals that live in large family groups consisting of several females and their offspring. They are non-territorial, and sometimes family groups can consist of as many as 40 individuals. Adult males are generally solitary and live separately rather than with the family group. Subadult males form bachelor groups for protection. However, they do maintain loose contact with the basic family group throughout the year.

They make firm nests in which to sleep by digging small trenches, using dry grasses and vegetation to line them. They sleep in these nests at night, but also retreat to these nests during the heat of the day,

The mating season starts during the end of winter, with males doing displays of strength against each other to achieve the right of mating. The gestation period varies according to the age of the expecting mother. For first-time breeders, it lasts 114 days, while it lasts 133 days in older ones. The average litter consists of 4–6 piglets, with the maximum being 10–12. The piglets are whelped in a nest constructed from twigs, grasses and leaves. These nests are similar to those used by them to sleep at night. Should the mother die prematurely, the piglets are adopted by the other sows in the sounder. Their average lifespan is between 8 and 14 years and they become sexually mature at two years old.


False fossa (Urvatrox tyrannica)
Order: Carnivora
Family: Herpestidae
Habitat: Forests and woodlands of Ngazidja Island
During their expansion, the humans had introduced several species. The Javan mongoose (Urva javanica) was left by them on the Comoros Archipelago, where they survived to the transition between the Holocene and Neocene. Their descendant is the false fossa, the great predator of the forests of Ngazidja, the largest island of the archipelago.

As their name says, the false fossa is morphologically similar to the Eupleridae predator that lived in Madagascar during the Holocene. Adults have a head-body length of 75 to 90 cm, with the males being larger than the females. It has semi-retractable claws (meaning it can extend but not retract its claws fully) and flexible ankles that allow it to climb up and down trees head-first, and also support jumping from tree to tree. This is an example of convergent evolution with their Malagasy distant relative. Their fur is dark reddish-brown, with a prominent black tip on their tails.

The false fossa is the top predator of Ngazidja. They feed on birds and mammals, including the dwarf hog and the fox civet. However, their main prey is the Spectacled lemur, which they actively hunt through the trees. While they can kill young and sick Ngazidja kangaroo-rat, the false fossa avoids healthy adults due to their powerful kicks and bites.

This species is active during both the day and the night, with activity peaks occurring early in the morning, late in the afternoon, and late in the night. The false fossa generally does not reuse sleeping sites, but females with young do return to the same den. The territory ranges of males and females overlap, but females usually have separated ranges. Except for mothers with young, these animals are usually found alone, so that the species is solitary.

The mating season starts during the spring. The males will enter the territory of a receptive female and when rivals find each other, they will vocalize and make antagonistic interactions. Occasionally those can end in violent fights. Females are pregnant for up to 90 days and give birth to a litter of 2 to 5 young, usually inside a concealed location, such as an underground den, a termite mound, a rock crevice, or in the hollow of a large tree. The newborns are blind and toothless. After about two weeks the cubs' eyes open, they become more active. The cubs do not take solid food until three months old, and do not leave the den until they are 5 months old. They are weaned shortly after that. After the first year, the juveniles are independent of their mother. Sexuall maturity is reached by about two years of age and their lifespan is of 18 years, but some males can die early due to wounds sustained during fights in the mating season.

Spectacled lemur (Eulemur elegantulus)
Order: Primates
Family: Lemuridae
Habitat: Forests and woodlands of Ngazidja
During their expansion, the humans had introduced several species. The mongoose lemur was left by them on the Comoros Archipelago, where they survived to the transition between the Holocene and Neocene. Their descendant is the spectacled lemur, an animal endemic to the forests of Ngazidja, the largest island of the archipelago. They are also the only species of lemur that live outside of Madagascar.

Spectacled lemur is a medium-sized lemur with a head-to-body length of 39 cm and a tail length of 55 cm. Like their ancestors, this species is sexually dichromatic. Males have a reddish-brown dorsal coat which darkens as it reaches the hands, feet and base of the tail. Ventral coat is pale gray and the tail is dark brown. The nose, muzzle and face are black, with white tufts in the ear and cheek. The females have a gray-brown dorsal coat which darkens to gray around the shoulders and upper area of the back to the top of the head. The ventral coat is a paler gray, and the face is black with white tufts in the cheeks and ear. Tail is often darker than the dorsal coat and can range in color from gray-brown to dark gray. Both sexes have white markings across its face, which gives them a "spectacled" appearance.

The diet of this species consists primarily of fruit, but includes other plant parts such as buds, young leaves and flowers, varying according to seasonal availability. It also includes occasional invertebrates. They can forage in the forest ground, but only do it in the presence of other animals such as the dwarf hog and the Ngazidja kangaroo-rat.

Spectacled lemur troop sizes range from 6 to 15 individuals, numbers varying depending on location. Each troop defends a territory of up to 15 hectares, and will chase off intruding groups with territory calls rather than defending home ranges violently. Differently from most of their relatives in Madagascar, their groups are led by a dominant male, who is the father of all young in the group. He will fight against solitary males that try to invade his territory.

They are the main prey of the false fossa. In the presence of these predators, they will flee through the trees with great agility.

Mating occurs in early autumn and births usually take place in early spring after a gestation of about 120 days. Typically only one young is born, but they can occasionally produce twins. As with most true lemur species, newborn Sanford's Lemurs cling to the mother's chest at first and after about two weeks they transfer onto her back. The young may be weaned by three or four months of age and they reach sexual maturity at two years. The males are expelled from the group at this age and they form bachelor gangs for protection against predators. This species has a lifespan of 20 years.

 Отправлено: 11.02.23 11:03. Заголовок: Interesting animals!..

Interesting animals!

цитата:

Differently from most of their relatives in Madagascar, their groups are led by a dominant male, who is the father of all young in the group.

What circumstances have led to this change?

 Отправлено: 11.02.23 12:55. Заголовок: медведь пишет: What..

медведь пишет:

цитата:

What circumstances have led to this change?

An intense intraspecific competition forced them to have the stronger male leading the group when fighting rivals for resources.

 Отправлено: 11.02.23 12:00. Заголовок: JOrnitho I like them..

JOrnitho
I like them.