Отправлено: 21.07.23 21:28. Заголовок: Naturalized species of the world

Since we had been talking about it these past days, I thought that we could have a topic only to talk about naturalized species that could leave descendants in the Neocene. I'll start by asking who could be the descendant of tall (megalocerus-sized) deer for the temperate forests of Southern South America, the red deer or the fallow deer? Both are introduced in Argentina and Chile.
Regarding competition with deermaras and local deers, its height will allow them to eat leaves from tall branches.

 Отправлено: 21.07.23 23:42. Заголовок: JOrnitho пишет: re..

JOrnitho пишет:

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red deer

Of course him!

 Отправлено: 22.07.23 00:00. Заголовок: wovoka пишет: Of co..

wovoka пишет:

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Of course him!

The males could have a crescent shaped antler and the name of the species could be Selene's deer, because of the Greek goddess of the moon.

 Отправлено: 22.07.23 00:57. Заголовок: Good name!..

Good name!

 Отправлено: 22.07.23 11:12. Заголовок: Good thread! I'm..

Good thread!
I'm good at fish, so I'll talk about them:
- Tilapias (Oreochromis sp.) across the world.
- Flowerhorn and red devil cichlids in South-East Asia (I already described this).
- Amur snakeheads (I already described this animal) and Asian carps in the USA
- Swarmp eels (Monopterus albus) naturalised at Everglades can escape to Cuba and live there.
- Clarias batrachus in USA. Author had already described wels catfish - like descendant of this fish living on Greater Antigua.
- Neogobius melanostomus in Quebec.
- Rotan (Percocottus glenii) at Russia. We already have described sone deccendants of this fish
- Sunfish (Lepomis gibbosus) in Europe. Also described.
- Pseudorasbora parva in Europe. Already described.
- Snakeheads at Central Asia. Already described.
- Goldfish and common carp (Cyprinus caprio) at Australia. Already described.
- Pacu at New Guinea. Already described.
- Common perch (Perca fluvatilis) at New Zealand (already described), Australia and SAR.
- Bass in Europe. Now it's not very common, but its invasion csn expand.
- Guppy and mosquitofish across the world. Many descendants of them ste already described.
Amphibians are not group with many invasive species, but I can mention koki and aga toad. I don't know about koki, but some aga descendants are already described.

 Отправлено: 22.07.23 15:25. Заголовок: лягушка пишет: I..

лягушка пишет:

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I'm good at fish, so I'll talk about them:

Good thinking! There is several species of fish that were introduced in other areas that can survive in the Neocene. I have some suggestions too:
The pacu in China, Southeast Asia and Florida
Peacock bass in Florida
Carassius auratus in several parts of the world in North America
Carassius gibelio in North America and Asia
Oncorhynchus mykiss in North America, Argentina and mountain rivers of Southeastern Brazil

Crustaceans we have the Pacifastacus leniusculus in Europe, Japan, and California
In amphibians we Xenopus laevis in North America, South America, Europe and Asia

 Отправлено: 22.07.23 16:39. Заголовок: JOrnitho Oncorhynch..

JOrnitho

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Oncorhynchus mykiss in...and mountain rivers

Salmo trutta is also invasive species in such habitats across the world.

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Crustaceans we have the Pacifastacus leniusculus in Europe

We also have Procamburus clarkii in Europe - it has naturalised there and even evolved into pale aqifer-dwelling form in Spain!

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Xenopus laevis

I don't knew about they were naturalised in such wide territory! Thank you!

 Отправлено: 22.07.23 18:53. Заголовок: лягушка пишет: Salm..

лягушка пишет:

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Salmo trutta is also invasive species in such habitats across the world.

They are also present in the Macaé River, in Rio de Janeiro.

лягушка пишет:

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We also have Procamburus clarkii in Europe - it has naturalised there and even evolved into pale aqifer-dwelling form in Spain!

It' s really interesting! There could be a species living in caves during the Neocene.

I finished the description of the descendant of red deer in Argentina and Chile:
Selene’s deer (Gigantocervus lunacornibus)
Order: Artiodactyla
Family: Cervidae
Habitat: Temperate broadleaf and mixed forests of Southern South America
As the greatest agent of environmental change in the Holocene, the humans hunted and extirpated several species from their natural ranges. They also introduced new species in different regions of the world, with many of them being capable of surviving well in these new areas. One of these species is the red deer (Cervus elaphus), this species from Eurasia was introduced in Chile and Argentina. This species survived the end of the Holocene and in the Neocene it gave rise to the Selene’s deer, a large inhabitant of the temperate broadleaf and mixed forests of Southern South America.
The Selene’s deer is one of the largest deers in the Neocene. A male has a head to body length of 300 cm and a height of 210 cm at the withers. The females are more modest, with 250 cm of head to body length and 198 cm in the shoulders. During the summer, their coat is reddish-brown with some few spots on the back. During the autumn, they grow thicker coats of hair, which helps to insulate them during the winter. Autumn is also when males grow neck manes. Males have stronger and thicker neck muscles than female deer, which may give them an appearance of having thick neck manes. During winter, their coat becomes dark chestnut brown and has a larger light brown rump-patch, with a yellowish throat. By the time summer begins, the heavy winter coat has been shed. These animals rub against trees and rocks to remove it. The only part of the body that remains with the same color during the entire year is the tail, which is white. A cursorial animal, these cervids have long legs that allow them to run away from predators.
Only the stags have antlers, which start growing in the spring and are shed each year, usually at the end of winter. They are crescent shaped, growing outwards and then inwards. The shape of their antlers is what names the species, since Selene was the ancient Greek goddess of the Moon. These antlers can reach 125 cm in some individuals. The upper tip of the antler is flattened and forked, with clashes between males resulting in the connection of these parts.
The Selene’s deer are ruminants and therefore have four-chambered stomachs. While they are mostly primary browsers, these deers can graze. They have a tendency to do most of their feeding in the mornings and evenings, seeking sheltered areas in between feedings to digest. Their diets vary somewhat depending on the season, with native grasses being a year-round supplement, tree bark being consumed in winter, and forbs and tree sprouts during the summer. Berries can also be consumed. Due to their height, these animals are capable of reaching tree branches to eat leaves, flowers and fruits. As a supplement for minerals, the Selene’s deer will lick rocks and munch bones.
Mature Selene’s deer usually stay in single-sex groups for most of the year. During the mating season, called the rut, mature stags compete for the attention of the hinds and will then try to defend the hinds they attract. Rival stags challenge opponents by belling and walking in parallel. This allows combatants to assess each other's antlers, body size and fighting prowess. If neither stag backs down, a clash of antlers can occur, and stags sometimes sustain serious injuries.
Dominant stags follow groups of hinds during the rut, from late summer into early winter. The stags may have as many as 20 hinds to keep from other, less attractive males. Only mature stags hold harems, and breeding success peaks at about eight years of age. Stags two to four years old rarely hold harems and spend most of the rut on the periphery of larger harems, as do stags over 11 years old. Young and old stags that do acquire a harem hold it later in the breeding season than those stags in their prime. Harem-holding stags rarely feed and lose up to 20% of their body weight. Stags that enter the rut in poor condition are less likely to make it through to the peak conception period.
They have a distinctive roar during the rut, which is an adaptation to forested environments. The male deer roars to keep his harem of females together. The females are initially attracted to those males that both roar most often and have the loudest roar call. Males also use the roar call when competing with other males for females during the rut, and along with other forms of posturing and antler fights, is a method used by the males to establish dominance. Roaring is most common during the early dawn and late evening.
The female reaches sexual maturity at 2 years of age. Selene’s deer mating patterns usually involve a dozen or more mating attempts before the first successful one. There may be several more matings before the stag will seek out another mate in his harem. Females in their second autumn can produce one or very rarely two offspring per year. The gestation period is 262 days. All calves are born spotted. After two weeks, calves are able to join the herd and are fully weaned after two months. The offspring will remain with their mothers for almost one full year, leaving around the time the next season's offspring are produced. They have a lifespan of 20 years.

 Отправлено: 22.07.23 19:54. Заголовок: JOrnitho Good deer!..

JOrnitho

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They are also present in the Macaé River, in Rio de Janeiro

Ok, I don't knew it.

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It' s really interesting! There could be a species living in caves during the Neocene.

I can describe it. Probably. Sometimes...

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Selene's deer

Good deer! I'll add it to list.

 Отправлено: 22.07.23 20:27. Заголовок: лягушка пишет: I ca..

лягушка пишет:

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I can describe it. Probably. Sometimes...

I'll make a description for the trout's in Brazil. Also, the Russian sturgeon was introduced in Uruguay and spread in Rio Grande do Sul, Brazil. You can see it in this article. Maybe it could survive in the Neocene?

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Good deer! I'll add it to list.

I also posted the description of a rodent and of the oryx in the topic about the Fauna of North America.

 Отправлено: 22.07.23 21:34. Заголовок: Selene’s deer (Gigan..

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Selene’s deer (Gigantocervus lunacornibus)

Interesting animal!

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The pacu in China, Southeast Asia and Florida

I do not think the Floridan ones will survive the Ice Age.

 Отправлено: 22.07.23 22:53. Заголовок: JOrnitho пишет: Sel..

JOrnitho пишет:

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Selene’s deer

Very interesting animal!

You also promised to describe giraffe like Antilope cervicapra in South American pampas.

 Отправлено: 23.07.23 00:13. Заголовок: wovoka пишет: You a..

wovoka пишет:

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You also promised to describe giraffe like Antilope cervicapra in South American pampas.

I'll work on this one next. I also thought about a descendant of the sheep living in the Patagonian steppes and being like a muskox.

 Отправлено: 23.07.23 01:48. Заголовок: JOrnitho пишет: I&..

JOrnitho пишет:

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I'll work on this one next.

I'll wait.

JOrnitho пишет:

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I also thought about a descendant of the sheep living in the Patagonian steppes and being like a muskox.

I remember that.

 Отправлено: 23.07.23 19:07. Заголовок: Another animal that ..

Another animal that could have descendants is the Vidua macroura. It was introduced in Portugal, California and Puerto Rico. To have it surviving, this bird would also need to practice broodparasitism in other local birds.

 Отправлено: 23.07.23 19:23. Заголовок: JOrnitho Yes, I thi..

JOrnitho
Yes, I think it's possible if this bird had successfully naturalised in places withoud its typical victims.

 Отправлено: 23.07.23 20:31. Заголовок: Yes, I think it'..

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Yes, I think it's possible if this bird had successfully naturalised in places withoud its typical victims.

In this case it may have many host species, like cowbirds that are not as specialized brood parasites as cuckoos.

 Отправлено: 24.07.23 03:22. Заголовок: медведь пишет: In t..

медведь пишет:

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In this case it may have many host species, like cowbirds that are not as specialized brood parasites as cuckoos.

The Vidua macroura parasitises Estrilda melpoda and Estrilda troglodytes that were also introduced in Puerto Rico. Estrilda melpoda was also introduced in Southern Californa, so we can think that the descendants of V. macroura here could parasitise the descendants of E. melpoda. The North American descendant of the pi-tailed could also whydah have evolved to parasitise Emberizidae, Passerellidae and Fringillidae that live in California.
Also, Vidua paradisaea was introduced in Japan and is thriving in the country, but I don't know if it'll go well after the Ice Age.
лягушка, what do you think of the Russian sturgeon that was introduced in Uruguay and spread in Rio Grande do Sul, Brazil? Could it survive?

 Отправлено: 24.07.23 10:57. Заголовок: JOrnitho what do yo..

JOrnitho

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what do you think of the Russian sturgeon that was introduced in Uruguay and spread in Rio Grande do Sul, Brazil? Could it survive?

I think they would survive - sturgeons are fast-growing fish that would have problems only with overfishing and habitate changes during ice age. But if sturgeons survive at South America they would live only as diminished freshwater forms and may expand at north.

 Отправлено: 24.07.23 11:53. Заголовок: лягушка пишет: I th..

лягушка пишет:

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I think they would survive - sturgeons are fast-growing fish that would have problems only with overfishing and habitate changes during ice age. But if sturgeons survive at South America they would live only as diminished freshwater forms and may expand at north

How large do you think that they can grow?

 Отправлено: 24.07.23 12:51. Заголовок: JOrnitho How large ..

JOrnitho

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How large do you think that they can grow?

Approximately 60 cm, I think.

 Отправлено: 25.07.23 04:23. Заголовок: лягушка пишет: Appr..

лягушка пишет:

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Approximately 60 cm, I think.

Ok! I think that, while they spend most of their lives in freshwater, they would still be able to move in estuarine regions.
Also, I finished the description of the blackbuck's descendant:

Yamanduntherium, the Beast of Yamandú (Yamaduntherium giraffoides)
Order: Artiodactyla
Family:Bovidae
Habitat:Savannas and open woodlands of Central and Southern South America
Among the damages caused by humans in nature, the introduction exotic species was probably one of the most disruptive. Several native animals and plants were outcompeted by the newcomers, disappearing completely from the face of Earth. With the arrival of the Neocene, the descendants of these exotic species had become part of the environment , completely integrated in the trophic relations. One of such cases is the yamandutherium, a descendant of the blackbuck (Antilope cervicapra) that was introduced in Argentina. An inhabitant of savannas and open woodlands of Central and Southern South America, the animal name means “the Beast of Yamandú” (Yamandú was one of the names of the supreme god of the tupi-guarani mythology).
The yamanduntherium is a large animal that evolved as an analogue to giraffes in South America. A fully grown specimen stands 450 to 600 cm and 250 cm to 350 cm at the shoulder, with males being far taller than the females. The largest female has a maximum height of 500 cm. Weighing close to 1,300 kg, males are also heavier than females. Much of their size comes from their long legs and neck, which can reach 250 cm. Different from giraffes, their body isn’t short, measuring 500 cm. Being more elongated, it gives a more “proportional” appearance to the animal. Also different from the Nanditherium of the Hindustan, the yamanduntherium is an elegant and agile animal, being able to run 70 km/h. The males have a two-tone colouration, with the upper parts and outsides of the legs being cinnamon brown, the underparts and the insides of the legs are all white. The head is darker, which contrasts with the white fur on the chin and around the eyes. The females and juveniles are yellowish-brown in the upper parts and become more yellowish-fawn in the belly and legs. The horns are only present in the males. They are short, being 60 cm long and straight with tips that are hooked. The tail is short.
This species survives primarily on a diet of leaves from several species of trees that are found in its habitats. They are able to pick food from tall trees, avoiding competition with smaller herbivores. Their long tongue is used to grasp branches and bring it to the month. Yamanduntherium will also eat fruits and seed pods.
Due to their size, an adult yamanduntherium have no predators. The newborns can be killed by large carnivores, but females will defend their offspring fiercely with kicks and stomps.
Females live in herds of 8 to 15 close related individuals. These groups are led by a matriarch and the other members are her sisters, daughters and their offspring. Adult males are solitary, but young individuals can form small groups of 5 individuals. The mating season happens during the end of winter and early spring. The males will establish a territory under the basis of the local distribution of female groups. While tolerant with each other during most of the year, the males become aggressive during the mating season. They actively defend resources in their territories, nearly 1.2 to 12 hectares in size. These areas are marked with scent using preorbital gland and interdigital gland secretions, feces and urine. While other males are not allowed into these territories, females are allowed to visit these places to forage. Rival males that invade these territories will be received with aggressive displays, such as kicks and loud grunts. However, direct disputes are rare. The males will stand in parallel, measuring each other. If they have similar sizes, they’ll bump against each other. Occasionally, bites can be given by the combatants in each other's necks. Due to their long necks, they can't use the horns in these disputes. Yamanduntherium can’t use the neck like how male giraffe’s used in intraspecific fights. This way, the horn is only a vestige of their ancestral lineage.
The gestation period of yamandutherium is on average 445-457 days, producing one offspring. Before the birth, the female will leave the herd. She will give birth alone and standing up, and the offspring will stand up anywhere between 5-20 minutes post-birth. Shortly after that, they will return to the herd. Weaning age of the young varies between 6-17 months, and independence occurs at 2 years old. Males leave the herd at this time, but females usually remain. These matriarchal herds can break into separate ones when the number of individuals there grows too much. Usually the new herd will follow a female that is older than its other members. Sexual maturity is reached within 5 years and they have a lifespan of 25 years.

 Отправлено: 25.07.23 10:14. Заголовок: Interesting animal!..

Interesting animal!

 Отправлено: 25.07.23 10:16. Заголовок: JOrnitho I think th..

JOrnitho

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I think that, while they spend most of their lives in freshwater, they would still be able to move in estuarine regions.

Yes, they can!
Antelope is good! I'll add t to list!

 Отправлено: 25.07.23 19:57. Заголовок: Very interesting ani..

Very interesting animal!

But:
JOrnitho пишет:

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Due to their size, an adult yamanduntherium have no predators.

I think this animal can be such a predator http://www.sivatherium.narod.ru/enmammal.htm#felinoraptor_tigrinus_en

 Отправлено: 25.07.23 21:47. Заголовок: wovoka пишет: think..

wovoka пишет:

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think this animal can be such a predator http://www.sivatherium.narod.ru/enmammal.htm#felinoraptor_tigrinus_en

I think that a full grown adult is too large to be preyed. However, the young aren’t so lucky and can be hunted by the raptor cats.

 Отправлено: 26.07.23 02:25. Заголовок: I finished the descr..

I finished the description of the descendant of the Russian sturgeon:
Southern sturgeon (Acipenser acanthodorsalis)
Order: Acipenseriformes
Family: Acipenseridae
Habitat: Freshwater and estuarine areas of Southern and Southeastern South America, from Paraíba do Sul River to estuaries in Tierra del Fuego. Also present in rivers and estuaries of Chilean Patagonia.
During the Holocene, humans had introduced species in new habitats due to different reasons. Some were introduced inadvertently, others as livestock, being new sources of food. The Russian sturgeon (Acipenser gueldenstaedtii) was produced in farms in Uruguay. From there, it was introduced accidentally in the Rio Negro, a tributary of the Rio de La Plata, and spread to Paraná River and reached Brazil. At the end of the Holocene, the fish had spread through the rivers and estuaries of the region. Now its descendant, the Southern sturgeon, is common to be found there. Being semi-anadromous, it inhabits freshwater and estuarine areas of Southern and Southeastern South America. This fish is one of the few sturgeon species that survived the anthropogenic onslaught.
The Southern sturgeon is small for the standard of sturgeons: their length ranges from 70 to 100 cm, but rarely surpass 90 cm. This small size is the result of bootleneck effect. Their ancestors were small sized Russian sturgeons that were ignored by fishers. As a good adaptation, genes for small body length were passed down to their descendants. Its morphology is similar to that of their ancestor, with a relatively short and rounded snout with three pairs of unfringed barbels closer to the tip of the snout than to the mouth. The dorsal fin has 30 to 48 soft rays and the anal fin has 23 to 35. The number of scales along the lateral line varies from 25 to 50. The upper surface is grayish-green, the lateral scales are pale and the belly white. What differentiates this species from their ancestor is that the dorsal scutes are elongated, having a spike-like appearance. These scutes are 16-24 in number and can reach 20 cm in length. Such structure helps the fish protect itself against predators.
This species feeds on crustaceans, molluscs, frogs and small fishes. Being capable of moving from freshwater to estuaries, the Southern sturgeon have a large number of prey at its disposal. To eat, these fishes will use its snout to probe the mud in the floor of rivers and estuaries. This process will scare the prey, which will be swallowed immediately.
Adult Southern sturgeons usually inhabit estuaries, but they can also be found in rivers. They reproduce during the spring. To spawn, they migrate upstream in rivers. There, they’ll lay the eggs in a hard substrate, which offers both support and cover to their sticky and adhesive eggs. Males attain sexual maturity at 12–16 years of age, whereas females do so at 16–22 years. They will spawn every four to seven years. Southern sturgeons could migrate up to 1,000 km upriver to spawn. The female lays her eggs on gravel from 4 to 40 m underwater. Upon hatching, the embryo is 11 to 14 mm long, and 10–14 days later when they absorb their yolk sack, the length is 18 to 20 mm. Thereafter, the larvae usually subsist on benthic invertebrates, but when reaching at least 10 cm in length, they will switch to a fish-based diet. While swimming back to the estuaries, the young sturgeon may cover up to 60 km a day. The Southern sturgeon can live for 45 years.

 Отправлено: 26.07.23 11:13. Заголовок: Interesting fish!..

Interesting fish!

 Отправлено: 26.07.23 12:14. Заголовок: JOrnitho Good fish!..

JOrnitho
Good fish!

 Отправлено: 27.07.23 01:20. Заголовок: I finished the descr..

I finished the description of the rainbow trout's descendant:
Red-bellied trout (Oncorhynchus macaensis)
Order:Salmoniformes
Family:Salmonidae
Habitat: Endemic to the Macaé River basin and its tributaries
The introduction of animals by humans in habitats that weren’t their own was one of the environmental calamities that affected the Holocene. These “invaders” outcompeted and preyed upon local fauna, leaving the trophic relations in disarray. With the arrival of the Neocene, the descendants of these became integrated in the ecological relations of these habitats. An example of it is the red-bellied trout, a descendant of rainbow trout (Oncorhynchus mykiss) that were introduced in the Macaé River in Brazil. This species evolved as an endemic fish of this river and its tributaries.
An adult red-bellied trout typically ranges from 30 to 61 cm, but may be up to 91 cm. The males are larger than the females. Adults are generally blue-green or olive green with heavy black spotting over the length of the body. They have a distinctive pale pink belly, which becomes bright red during the breeding season. Until reaching their first year, the young have silver bellies with faint pink tones and a dark circle in their caudal fin that becomes pale gray in adults.
These fishes are predators with a varied diet and will eat nearly anything they can capture. Red-bellied trout routinely feed on larval, pupal, and adult forms of aquatic insects. They also eat fish eggs and adult forms of terrestrial insects (typically ants, beetles, grasshoppers, and crickets) that fall into the water, as well as algae. Other prey includes small fish up to one-third of their length and crustaceans.
The red-bellied trout spawn during the rainy season, with the adults migrating upstream in search of shallow waters with gravel bottoms. The trout form schools of thousands of fishes and several predators are attracted by this migration, using this “trout run” or “piracema” (a Tupi name for the migration of fish upstream to spawn) to catch these fishes in great abundance. Unlike some salmon, this trout is able to spawn several times. After the spawn, the adults will return to the river’s basin.
Spawning sites are usually a bed of fine gravel in a riffle above a pool. The female clears a redd in the gravel by turning on her side and beating her tail up and down. They usually produce 2000 to 3000 eggs per kilogram of weight. During spawning, the eggs fall into spaces between the gravel, and immediately the female begins digging at the upstream edge of the nest, covering the eggs with the displaced gravel. As eggs are released by the female, a male moves alongside and deposits sperm over the eggs to fertilize them. The eggs usually hatch in about four to seven weeks although the time of hatching. In approximately two weeks, the yolk sac is completely consumed, and fry commence feeding mainly on zooplankton. The growth rate of red-bellied trout varies with quality and quantity of food. The red-bellied trout have a lifespan of 10 years, but many perish early and during the migration.

 Отправлено: 27.07.23 09:53. Заголовок: JOrnitho Red-bellie..

JOrnitho

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Red-bellied trout

Good trout! I like this!

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I found this article about exotic fishes in southern Brazil

I agree to you about Cyprinus carpio, Coptodon rendalli (and also other tilapias from Oreochromis genus) and Micropterus salmoides, but I think Clarias sp., Ctenopharyngodon idella, Hypophthalmichthys molitrix, Hypophthalmichthys nobilis (in USA they're united under common name "asian carp"), and Ictalurus punctatus also can survive - they are invasive species that became a problem at many parts of the world.

 Отправлено: 27.07.23 12:59. Заголовок: лягушка пишет: I ag..

лягушка пишет:

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I agree to you about Cyprinus carpio, Coptodon rendalli (and also other tilapias from Oreochromis genus) and Micropterus salmoides, but I think Clarias sp., Ctenopharyngodon idella, Hypophthalmichthys molitrix, Hypophthalmichthys nobilis (in USA they're united under common name "asian carp"), and Ictalurus punctatus also can survive - they are invasive species that became a problem at many parts of the world.

What do you think if one of the Hypophthalmichthys becomes goldfish-sized? It could be a dwarf species of carp.
Also the salmon Oncorhynchus tshawytscha was introduced in Patagonia and is now thriving in the region, going to the sea and returning to spawn in local rivers. Do you think that it could survive in the Neocene?
I had another idea: the pacus introduced in Southeast Asia would evolve in a piranha-like species, while other would remain like their ancestors. Do you think that it's plausible?

 Отправлено: 27.07.23 13:37. Заголовок: JOrnitho What do yo..

JOrnitho

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What do you think if one of the Hypophthalmichthys becomes goldfish-sized? It could be a dwarf species of carp.

But why? Niches of small cyprinids in South America are already occupied by characiniform fish, and also I think that downsizing won't be good fpr this fish - smaller size means more predation.

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Also the salmon Oncorhynchus tshawytscha was introduced in Patagonia and is now thriving in the region, going to the sea and returning to spawn in local rivers.

I think chinook salmon can survive in Patagonia and New Zealand, but only if it wouldn't be overfished by humanity during its decline (at first page of neocene project were said that humanity collapsed into mediveral level before dying out).

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I had another idea: the pacus introduced in Southeast Asia would evolve in a piranha-like species, while other would remain like their ancestors. Do you think that it's plausible?

Pacus already evolved into carnivorous forms in Meganesia, so they can do it in S.E. Asia.

 Отправлено: 27.07.23 14:26. Заголовок: лягушка пишет: But ..

лягушка пишет:

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But why? Niches of small cyprinids in South America are already occupied by characiniform fish, and also I think that downsizing won't be good fpr this fish - smaller size means more predation.

I see. How do you think that their descendants will be?
I already had some ideas for the Micropterus salmoides (an analogue of Amazonian peacock bass in temperate rivers) and the Cyprinus carpio (as a classic carp).

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I think chinook salmon can survive in Patagonia and New Zealand, but only if it wouldn't be overfished by humanity during its decline (at first page of neocene project were said that humanity collapsed into mediveral level before dying out).

If humanity collapsed into Medieval level, it means that they'll not be able to used modern ships and industrial machines to fish salmon in large scale. This way there'll be less pressure over them. I think that populations in Patagonia and New Zeland would survive because of it, but they would be affected by the bootleneck effect because there would be a reduction in their population, before it grew up again.

 Отправлено: 27.07.23 15:49. Заголовок: JOrnitho How do you ..

JOrnitho

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How do you think that their descendants will be?

They can stay ancestor - like and even become bigger to protect itself from predators. They reproduction and diet would stay unchanged.

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but they would be affected by the bootleneck effect because there would be a reduction in their population, before it grew up again.

Ok, I understand it.

 Отправлено: 27.07.23 16:07. Заголовок: лягушка пишет: They..

лягушка пишет:

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They can stay ancestor - like and even become bigger to protect itself from predators. They reproduction and diet would stay unchanged.

Ok!
Is there other species of salmon alive in the Neocene? I want to mention this information when doing the description of the chinook's descendant.

 Отправлено: 27.07.23 19:52. Заголовок: JOrnitho Is there o..

JOrnitho

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Is there other species of salmon alive in the Neocene? I want to mention this information when doing the description of the chinook's descendant.

Grayling (Thymallus sp.) are still alive at the Neocene, some species of Savelinus also can survive.

 Отправлено: 27.07.23 02:25. Заголовок: лягушка I found this..

лягушка
I found this article about exotic fishes in southern Brazil. Which one of these do you think that could survive in the region? I think that Cyprinus carpio, Coptodon rendalli and Micropterus salmoides are good candidates.

 Отправлено: 27.07.23 11:09. Заголовок: Interesting fish!..

Interesting fish!

 Отправлено: 28.07.23 04:34. Заголовок: I finished the descr..

I finished the description of the Patagonian salmon. I'll work on the description of the New Zealand species next.

Emperor salmon (Oncorhynchus imperator)
Order:Salmoniformes
Family:Salmonidae
Habitat: South Atlantic and Pacific oceans, including the Antarctic Ocean. Adults spawn in rivers of Southern South America, from Tierra del Fuego to Maipo River in the West side of the continent and to Jacuí River in the East side.
During the Holocene, humans had introduced species in new habitats due to different reasons. Some were introduced inadvertently, others as livestock, being new sources of food. The Chinook salmon (Oncorhynchus tshawytscha) was introduced in South America with the purpose of being produced as a food source. Inevitably, some individuals escaped and started to reproduce in Patagonia. During the decline of humanity, this species suffered pressure as a source of food, due to having stayed mostly in freshwater during the planktonic collapse, but was able to survive and their population recovered. However, its decline and eventual recovery resulted in a bootleneck effect over these fishes. Due to that, its descendants' genetic pool comes from a small number of survivors.
In the Neocene, the Chinook salmon gave rise to the Emperor salmon, an inhabitant of cold waters of Southern Oceans. The adults spawn in rivers of Southern South America, from Tierra del Fuego to Maipo River in the West side of the continent and to Jacuí River in the East side.
An adult emperor salmon has an average length of 70 to 120 cm, but the maximum length is about 150 to 180 cm. This fish is blue-green on the back and on the top of the head, with white ventral surfaces. They have a red stripe that runs on their sides, from the posterior part of the eyes to the base of the tail. This strip becomes brighter during the breeding season. It has black spots on its tail and the upper half of its body. The tail is silver.
The diet of the emperor salmon varies according to their age. Juvenile fishes eat zooplankton, insects and even ctenophores. As adults, they eat smaller fish. Among the predators of this species are seabirds, larger fishes and squids. The young are among the preferred prey of Southern sturgeons that inhabit Patagonian rivers.
Like their ancestors, the emperor salmon is euryhaline, and thus live in both saltwater and freshwater environments throughout their life. Once hatching, they spend three to twelve years in the ocean before returning to their home rivers to spawn. The salmon undergo radical morphological changes as they prepare for the spawning event ahead. Salmon lose the silvery blue they had as ocean fish, and their color darkens, sometimes with a radical change in hue. Emperor salmon is sexually dimorphic, with the male developing canine-like teeth, and their jaws develop a pronounced curve or hook called a "kype”. A more dominant male salmon have a reproductive advantage as females are often more aggressive toward smaller males.
Like their ancestor, the emperor salmon spawn in larger and deeper waters. They can be found in the spawning areas from late summer to early winter. The female salmon may lay her eggs in four to five nesting pockets. After laying eggs, females guard the nests from four to 25 days before dying, while males seek additional mates. The eggs hatch 90 to 150 days after deposition, depending upon water temperature. Egg deposits are timed to ensure the young salmon fry emerge during an appropriate season for survival and growth. Fry and young fishes usually stay in fresh water for 12 to 18 months before traveling downstream to estuaries, where they remain as smolts for a year. After this period, they depart to the open sea. Some individuals return to freshwater one or two years earlier than their counterparts. They are typically less than 61 cm long but are sexually mature. The lifespan of the emperor salmon is twelve years, the age that most of them return to spawn and die shortly after. They are parasited by Myxozoans.

 Отправлено: 28.07.23 07:53. Заголовок: JOrnitho Good fish!..

JOrnitho
Good fish! Looks like Oncorhynchus rastrotus.
And also add the fact that they stayed into fresh waters during planktonic disaster and survived due that.

 Отправлено: 28.07.23 10:47. Заголовок: Interesting fish!..

Interesting fish!

 Отправлено: 28.07.23 13:54. Заголовок: лягушка пишет: And ..

лягушка пишет:

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And also add the fact that they stayed into fresh waters during planktonic disaster and survived due that.

Added it!
I also added some informations in the Southern sturgeon, including some changes in its size. I made it a bit larger (maximum of 100 cm), because its the predator of the emperor salmon. I explained their size with the bootleneck effect.

 Отправлено: 28.07.23 16:08. Заголовок: JOrnitho Ok, thank ..

JOrnitho
Ok, thank you!

 Отправлено: 29.07.23 15:45. Заголовок: I finished the descr..

I finished the description of the New Zealand salmon:
Flag-finned salmon (Oncorhynchus vexillipinna)
Order:Salmoniformes
Family:Salmonidae
Habitat:South Pacific and Antarctic Ocean, adults spawn in rivers of New Zealand.
During the entire Holocene, the introduction of exotic animals as new sources of food was common. The Chinook salmon was reproduced in fish farms of New Zealand, but some individuals escaped and started to reproduce in nature. While the decline of humanity had caused the exploitation of these populations, the salmon was able to survive in the Neocene. However, there was a consequence: there is bootleneck effect over these fishes. The flag-finned salmon is their descendant, an inhabitant of South Pacific and Antarctic Ocean, with adults spawnings in rivers of New Zealand.
The flag-finned salmon is small when compared to its ancestor, with an average size ranging from 65 to 85 cm. Such small size is one of the results of the bootleneck effect: the individuals that were ancestors to this species were small, with their size having allowed them escape the anthropocenic pressure. Then, they passed down the genes of size to their descendants. They are reddish-purple on the back and on the top of the head, with silvery sides and white ventral surfaces. When they move into fresh water the color changes to dark olive green and the belly color deepens. It has black stripes on its tail and the upper half of its body. Their most distinctive feature is their 30 cm long dorsal fin. Both the dorsal and caudal fins have yellow and silvery-blue color, which become brighter during the breeding season. Spawning males typically grow an elongated snout or kype, their lower fins become tipped with white and they have enlarged teeth.
Juvenile flag-finned salmon eat zooplankton and insects. They will also eat ctenophores. As adults, they eat smaller fish. On the other hand, the salmon is the prey for several other species, from sea birds to larger fishes and squids.
Most flag-finned salmon spawn during late summer and early winter in small streams and intertidal zones. Some travel more than 3,200 km upstream to find perfect spawning areas. The fry migrate out to sea from early spring through summer, almost immediately after becoming free swimmers. They spend three to seven years traveling very long distances in the ocean, reaching as far South as Antarctica. They die about two weeks after they return to the freshwater to spawn. They utilize the lower tributaries of the watershed, tend to build nests called redds, really little more than protected depressions in the gravel, in shallow edges of the watercourse and at the tail end of deep pools. The female lays eggs in the redd, the male sprays milt on the eggs, and the female covers the eggs with gravel. The female can lay up to 4000 eggs.

 Отправлено: 29.07.23 17:49. Заголовок: JOrnitho Good fish!..

JOrnitho
Good fish!

 Отправлено: 29.07.23 21:43. Заголовок: Interesting fish!..

Interesting fish!

 Отправлено: 30.07.23 02:31. Заголовок: Finished the descrip..

Finished the description of a descendant of an exotic fish:
Greater chinese tambaqui (Sinocolossoma major)
Order:Characiformes
Family:Serrasalmidae
Habitat: Poyang Lake, Yangtze and Yellow rivers and their tributaries.
During the entire Holocene, the introduction of animals by humans in habitats that weren’t their own was a common practice. The tambaqui (Colossoma macropomum) from South America was introduced in fish farms of China, but some individuals escaped and were able to survive in nature. In the Neocene, they give rise to the genus Sinocolossoma, with the greater chinese tambaqui being its type species. This species inhabits the Poyang Lake, Yangtze and Gan rivers and their tributaries.
The greater chinese tambaqui is a large fish, with 150 cm of length and 50 kg. It is similar in shape to their ancestor, being tall and laterally compressed with large eyes and a slightly arched back. The teeth of the greater chinese tambaqui are molar-like, an adaptation for crushing plant seeds and nuts. The lower half of its body is mainly blackish, while the remaining is olive. The pelvic, anal and small pectoral fins are white.
This species consumes fruits and seeds, especially from woody angiosperms and herbaceous species. Depending on the quantity and food quality of these foods, it causes the fish to decide on the location of their habitat. Zooplankton, insects, snails, shrimps, small fish, filamentous algae and decaying plants are consumed.
The greater chinese tambaqui is mostly solitary, but it migrates in large schools. During the non-breeding season, adults stay in flooded areas. They stay there for four to seven months during the flood season, but as the water level drops they move into the main river channels or to a lesser extent floodplain lakes. At the start of the next flood season, large schools move into rivers where they spawn. The spawning location is along woody shores or grassy levees. The schools then break up as the adults return to the flooded forest of white, clear and blackwater rivers, and the annual pattern is repeated. Juveniles stay near macrophytes year-round, only switching to the adult migration pattern when reaching sexual maturity. Maturity is reached at a length of about 60 cm. The species regularly reaches an age of 40 years.
The lesser chinese tambaqui (Sinocolossoma minor) is a closely related species. This species inhabits the Gan Jiang and Yuanshui rivers. They have 110 cm of length and 40 Kg. Their morphology is similar to that of their larger relative, with the exception of their belly that is white and fins that are black.

 Отправлено: 30.07.23 10:14. Заголовок: Interesting fish!..

Interesting fish!

 Отправлено: 30.07.23 17:55. Заголовок: JOrnitho Greater ch..

JOrnitho

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Greater chinese tambaqui

Good fish!
About coypu: yes, it can survive in Kenya and China, and also in Europe where it also were introduced. However, I described beaver-rat - coypu-like descendant of Thryonomys from Land of Zinj. How we can ecologically split them?

 Отправлено: 30.07.23 14:56. Заголовок: I found this article..

I found this article about the distribution of Myocastor coypu in areas where it was introduced. Where do you think that it can survive? Maybe Kenya and China?

 Отправлено: 30.07.23 18:57. Заголовок: лягушка пишет: Abou..

лягушка пишет:

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About coypu: yes, it can survive in Kenya and China, and also in Europe where it also were introduced. However, I described beaver-rat - coypu-like descendant of Thryonomys from Land of Zinj. How we can ecologically split them?

For China, I thought that it could have evolved as an analogue to the extinct Castoroides. It would be very large and eating aquatic plants in lakes and rivers, such as the Yangtze.
The African one could have evolved to be small, perhaps like an Oryzomys palustris.
For China, I thought that this rat could have evolved

 Отправлено: 31.07.23 08:52. Заголовок: JOrnitho Good ideas..

JOrnitho
Good ideas!

 Отправлено: 31.07.23 21:58. Заголовок: лягушка Some species..

лягушка
Some species of fish that could evolve in South America:
-Pangasius hypophthalmus in rivers of the Amazon rainforest
-Parachromis managuensis in São Francisco and Parnaíba rivers
-Oreochromis in coastal waters. Schools of this genus are found in estuaries and saltwater in Brazilian coast.