in the course of fish evolution, two of the gill slits slowly advanced into the jaws.
The evolution of fish started about 530 million years in the past at some point during the Cambrian explosion. It become during this time that the early chordates advanced the cranium and the vertebral column, main to the first craniates and vertebrates. the first fish lineages belong to the Agnatha or jawless fish.
The earliest fish, corresponding to living hagfish, developed about 550 million years in the past. Diversifications that in the end advanced in fish include an entire vertebral column, jaws, and an endoskeleton manufactured from bones in preference to cartilage. Fish live in the course of the sea and in freshwater lakes and streams.
New studies have uncovered the genetic foundation of gill covers in fish, which came about over 430 million years ago. It sheds light on one of the most essential evolutionary traits for fish, in addition to over vertebrates.
In jawless fishes, a sequence of gills opened behind the mouth, and those gills became supported by way of cartilaginous elements. the primary set of these elements surrounded the mouth to shape the jaw.
Learn more about the evolutions of fishes here: brainly.com/question/1426050
#SPJ4
Answer:
The sex ratio is the ratio of males to females in a population.
Explanation:
It is generally divided into four subdivisions:
primary sex ratio — ratio at fertilization
secondary sex ratio — ratio at birth
tertiary sex ratio — ratio in sexually mature organisms
quaternary sex ratio — ratio in post-reproductive organisms
Answer:
School Psychologist
Explanation:
School psychologists: The school psychologists tend to work with students and a specific group of students to work on disabilities, academic difficulties, behavioral problems, and other related issues.
School psychologists also engage themselves with parents and teachers to create techniques to deal with the classroom and home behaviors. They help the students or the child to deal with emotional disturbances, for example, suicidal thoughts. They work mostly in private schools, hospitals, and clinics, community agencies, etc.
In the question above, the given statement represents the school psychologist.