Hybridizing blind cave fish from different cave populations can partially restore the vision of their offspring
, biologists have found. The study suggests that genetic engineering can override, at least in part, half a million years of evolutionary change in one generation.
Can blind cave tetras see?
The blind cave tetra is not always completely blind, but it often loses its sight slowly after hatching
. Different populations of blind cave tetra have different levels of blindness – some have limited sight while others lose their sight completely and their eyes become covered over, leaving them totally blind.
Do blind cave fish need eyes?
Cave shrimp and cave fish don't… because
they don't have eyes
. Energy-saving eye loss, or the expensive tissue hypothesis, is one of a number of theories to explain why sighted animals that took up life inside caves evolved to be blind.
Do cave fish lose their eyes?
Blind cavefish (Astyanax mexicanus)
lose critical eye tissues within a few days after their eyes begin to develop
. According to a new study, this loss of eye tissues happens through epigenetic silencing of eye-related genes.
How do Mexican cavefish see?
The Mexican blind cavefish does not have eyes, but it can “see” obstacles in dark caves by
puckering its mouth and producing bursts of suction
, according to a new study. The research describes this unique form of navigation for the first time.
Are cave fish and minnow common ancestry?
The appearance of the cavefish and the minnow suggests a common ancestry
since they possess homologous structures. Based on observations made on the characteristics of the cavefish and minnow, the structures of the fins, tails, and overall shape of the bodies make the two types of fish seem exceedingly related.
How long do blind cave tetra fish live?
Blind Cave Tetra Appearance
The Blind Cave Tetra have pink pigmentation with silver lines on their body. They can live
up to 5 years
.
Do blind cave tetra need a filter?
When it comes to water acidity, it should be held between 6.5 and 8.0 pH. The water shouldn't be soft at all, as Blind Cave Tetras prefer it to be hard or moderately hard.
The filter is very important
so don't shy away from buying a high-quality one that does a good job keeping the water clean.
How do you feed blind cave fish?
The blind cave tetra primarily feeds on insects, crustaceans and worms in the wild, though they will accept a wide range of prepared foods in the home aquarium.
Their diet should consist of a high quality flake food, and I personally recommend New Life Spectrum pellets
.
What is the most important adaptation of a cave fish?
Cavefish adaptations include constructive traits, such as
more taste buds and cranial neuromasts
, increased olfactory capacity, and fat deposits, which facilitate feeding and survival during times of low food input, and regressive traits, such as decreased metabolic rates and loss of eyes, which may be important in …
Why is eyesight not important adaptation to life in a cave?
Explain why eyesight is not an important adaptation to life in a cave.
There is NO light in a cave
. All living things need light to see. Eyesight is not a sense that the cave fish can use in darkness.
Why do cave fish have no eyes?
mexicanus is the result of natural selection, pleiotropy, and genetic drift, not individual effort. Natural selection gives organisms what they need. “The fish need to save energy so they lose their eyesight.” “The fish lose their eyes
because they don't need them
.”
Why do Catfish lose their eyes?
The neutral mutation hypothesis is based on the fact that natural selection does not just reward success but also weeds out failures. Many cave fishes are blind, and an experiment carried out by scientists suggests that
blindness in these fishes is the result of a mutation that also improves their sense of smell
. 6.
How big do blind cave tetras get?
Believe it or not, your Mexican tetra fish tank technically can look and function like any conventional freshwater fish aquarium Blind cave tetras are appropriately sized for most tanks, generally growing to adult lengths of
less than 4 inches
. Up to a half-dozen may be kept in 20-gallon tank.
What do blind cave fish eat?
Diet: The Blind cavefish is mainly carnivorous, feeding on
aquatic worms, snails, small fish and insects
. Somewhat omnivorus in that they will also eat algae and plant matter. live in the dark.
How do blind cave fish survive?
Mexican cavefish survive starvation
with the help of a genetic mutation that makes them gain weight
. Despite prolonged food shortages in their subterranean homes, some Mexican cavefish (Astyanax mexicanus) live just as long as close relatives that dwell in rivers above ground.
What is the difference between a cave fish and a minnow?
The minnow is found in open streams and has excellent eyesight. The cave fish is found in dark, cave streams. It is blind and has reduced, non-functioning eye parts.
What does it mean if structures are homologous?
Homologous structures are
similar physical features in organisms that share a common ancestor, but the features serve completely different functions
. An example of homologous structures are the limbs of humans, cats, whales, and bats.
What do you think has become the most important adaptation of the cave fish think about senses )? Explain your answer?
The lateral lines are enhanced by structures called neuromasts, specialized hair cells running along the lateral line to enhance sensory abilities. Cavefish rely heavily on
vibration attraction behavior
to sense the location of potential prey, and will move towards vibrations in the water.
What do Mexican tetra eat?
In the winter, some populations migrate to warmer waters. Its natural diet consists of
crustaceans, insects, and annelids
, although in captivity it is omnivorous. The Mexican tetra has been treated as a subspecies of A. fasciatus, but this is not widely accepted.
Where does the surface Mexican tetra live?
Native Range:
Subtropical America. Mostly eastern and central Mexico and also the lower Rio Grande, lower Pecos, and Nueces rivers in Texas
(Lee et al.
Do blind cave fish eat other fish?
Although some will learn to eat off of the surface of the water, most will root in the substrate for food. They do very well on sinking food. They will eat anything that they can get a hold of from flakes, pellets, to live foods.
They will also eat any eggs from other fish that may be in the substrate
.
