After a summer without jellyfish, and the enormous size of the jellyfish in the winter swarms, we anticipate that the coming summer will be relatively abundant in jellyfish," said Dr. Dor Edelist, a marine biologist from the University of Haifa
Jellyfish of the "wandering filament" species of unprecedented sizes, with the largest measured exceeding 30 kilograms, have been observed in recent days along the coasts of Israel, after a summer and fall completely devoid of jellyfish. "Winter swarms of threadworms have been commonplace in recent years, but this year the size of the jellyfish is definitely unusual. After a summer without jellyfish, and the enormous size of the jellyfish in the winter swarms, we expect that the coming summer will be relatively abundant in jellyfish", said Dr. Dor Edelist, a marine biologist, from the AMBER Laboratory at the University of Haifa.
According to Dr. Edelist, one of the founders of the civic science site "Medusas in the Nation" along with Prof. Dror Angel from the University of Haifa, there are several possible explanations for the giant jellyfish phenomenon, the main of which relates to the impressive amounts of precipitation this winter, which brought many fertilizers to the sea. As a result, the production of algae developed, followed by a bloom of the zooplankton that feeds on them, and finally the jellyfish that feed on it. "The last time we had such a phenomenon, of a summer without jellyfish followed by developed winter swarms, was in 2016-7 and after that we experienced intense summer swarms in the summer of 2017, so we also expect a significant bloom in the summer months of June and July," said Dr. Edlist.
More of the topic in Hayadan:
3 תגובות
There is a string attack and there is a string jellyfish attack
Jellyfish or geometry the voter will choose
After 2000 years a new geometry was born.
A line is a basic geometric concept, and it has two data - length and shape.
There are 3 forms of lines that people notice.
An open straight line that has no beginning and no end,
Open curved lines that have a beginning, but no end.
and closed circular lines whose length is between zero mm and infinity mm.
Joining lines creates a geometric shape.
The simplest geometric shape created by such a combination is that of 2 straight lines going out from the same point in two other directions.
This simple geometric shape is given the name angle.
An angle is a visually distinct shape, and there are many shapes of angles.
An ID number can be attached to each shape of an angle.
To obtain an identification number of an angle, a closed circular line must be drawn on it, the center of which is at the point of contact of the straight lines forming the angle.
This closed circular line has an unknown millimeter length (a), and a small part of the length of a (which will be marked with the letter b) is between the two straight lines that are the bisectors of the angle.
It should be noted that there is no measuring device for the length of a circular line.
Therefore, the exact millimetric lengths (a) (b) exist in reality, but cannot be arrived at by measurement.
What is certain is - that millimeter length A is greater than millimeter length B.
If we knew the exact millimetric lengths (a) (b), then it is possible to arrive at the number of the shape of this angle, by an arithmetic operation of division.
Number of millimeter length b divided by number of millimeter length a.
It must be remembered that an angle is a shape, and therefore is not a quantitative concept.
Therefore, there is no point in talking about a small or large angle,
An angle is a shape formed by two straight lines that depart from the same point in two other directions, so there are infinite shapes of angles.
Compared to the angle which is a pure shape, the line has length and shape.
A line is a basic geometric concept, and it has two data - length and shape.
There are 3 forms of lines that people notice.
An open straight line that has no beginning and no end,
Open curved lines that have a beginning, but no end.
and closed circular lines whose length is between zero mm and infinity mm.
Closed circular lines have many forms of curvature,
The millimetric length of a closed circular line determines the shape of its curvature.
The shorter a closed circular line, the greater its shape of curvature.
The longer a closed circular line, the smaller its shape of curvature.
For the shape of the curvature of a closed circular line, it is possible to fit a number .
The number of the shape of the curvature of a closed circular line, will be obtained from the number of measured length of a closed circular line, divided by the number of measured length of a straight line - crossing the closed circular line, into two equal parts.
Since there is no device for measuring the length of a closed circular line, it is not possible to obtain the number of the shape of the curvature of a closed circular line.
This number has attracted the attention of mathematicians since the time of Archimedes, and they agreed that it is a number slightly larger than 3
They also decided that the infinite curvature of closed circular lines is of no importance and that this number, which is a little larger than 3, will suit all of them.
With this unfortunate decision, geometry froze for 2000 years, until the year 2017
In this year, the scope experiment was conducted, which includes a very precise measurement that determined:
Each millimeter length of a closed circular line has a specific curvature shape number, which is between 3.14 and 3.16
This is how a new geometry of closed circular lines came into the world.
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