Crucian Carp are not a part of the gold fish family. In fact they are currently a totally different species. However, historical research done by Japanese and Chinese historians as gold fish enthusiasts have uncovered information that leads everyone to accept that this stock is the source stock. Have they truly evolved? Or is there ad hoc reasoning drawing uneducated conclusions.
Being a goldfish breeder does not make one a geneticist.
Before modern mutations in the evolution of crucian carp themselves, these creatures were in-fact the type of carp that produced the initial yellow tint in the other wise gray carp breed into goldfish.
Crucian Carp in a fishtank
This breeding occurred by popular damming of the colorful variety into ponds and rice patches.
By the Song Dynasty the divergence of goldfish from gray carp and world dominant Crucian carp (the source of the yellow tint) was complete: A process that had begun to be a fade during the preceding Tung dynasty.
Crucian carp now represent all over the world, and they are kept in water gardens as pets. Koi, gold fish, and are more colorful. For this reason they are more often found in water gardens.
Crucian carp have been on the evolutionary move since the off shoot of goldfish, koi, and others.
They are much more hearty than many other fish. Although they often have a disk shape, more recent generations have grown longer in the wild making it more difficult for predators to swallow them.
They have been displaying a strong heterosis. Which means they are much smarter than their ancestors and even there parents were.
This means that they will out eat, live, and breed other local carp populations world wide.
In 2005 Crucian carp were observed to be the species with the tenth highest reproduction rate world wide.
To this point the research holds up to common sense scrutiny.
The physical attributes that many ‘experts’ claim to be markers of there external difference as a species from goldfish is not yet conclusive.
Things as simple as markings that disappear with age do NOT mean that a creature is a different species. This is what would be implied if this is one of the only definitions separating Crucian Carp from wild gold fish.
Crucian carp are not a different species simply due to fading markings, and small facial or fin variants. Look at the variants between gold fish.
The standard is if the off spring cannot reproduce after many natural pairings have been observed for several generations. Then it is a different species.
The Crucian carp is a wonderful addition to any water garden. How different they are from the carp sequestered in the ponds of the Tung Dynasty needs to be more publicly documented so the data can be scrutinised for motivation behind the research before it is widely accepted as fact that can be allowed to drift into what common sense takes for granted: Or loosely denoted as fact on wikipedia without greater scrutiny.
These beautiful fish are still yet to be proven a different species that carassius gibelio, (the wild gold fish) with greater clarity.
The Crucian carp (carassius carassius) is proving to be the heartiest of all the water garden species, or races. Not to mention they are kind of cute.
