Related Experiment Video
Updated: Jul 28, 2026
07:25
Basic Methods for the Study of Reproductive Ecology of Fish in Aquaria
Published on: July 20, 2017
Reproduction and level of intelligence
S Nyström1, L O Bygren, D R Vining
1Department of Environmental Hygiene, Göteborg University, Sweden.
Scandinavian Journal of Social Medicine
|September 11, 1991
Summary
This study found no link between intelligence (IQ) and the number of children people have in a Swedish population. Researchers analyzed IQ scores and family size in over 3,000 individuals.
Area of Science:
- Demography
- Human Intelligence
- Population Studies
Background:
- Understanding the relationship between cognitive ability and reproductive behavior is crucial for demographic and sociological research.
- Previous studies have yielded mixed results regarding the association between intelligence and fertility.
Purpose of the Study:
- To investigate the association between intelligence quotient (IQ) and the mean number of children in a representative Swedish population sample.
- To contribute empirical data to the ongoing discussion on intelligence and reproductive patterns.
Main Methods:
- A population sample of 3,064 individuals from a Swedish rural-urban setting was utilized.
- Intelligence (IQ) was assessed using a single, well-established psychometric procedure.
- Statistical analysis was performed to determine the mean number of children per individual and correlate it with IQ levels.
Main Results:
- No systematic association was observed between individuals' IQ levels and the mean number of children they had.
- The findings indicate that cognitive ability, as measured by IQ, does not appear to be a significant determinant of family size in this population.
Conclusions:
- The study concludes that intelligence, as measured by IQ, is not systematically associated with reproductive behavior in the studied Swedish population.
- These findings suggest that other socioeconomic, environmental, or cultural factors may play a more significant role in shaping fertility decisions.
More Related Videos
09:23Quantification of Information Encoded by Gene Expression Levels During Lifespan Modulation Under Broad-range Dietary Restriction in C. elegans
Published on: August 16, 2017
06:38Determination of Reproductive Competence by Confirming Pubertal Onset and Performing a Fertility Assay in Mice and Rats
Published on: October 13, 2018
Related Concept Videos
01:27Reproductive Cloning
Reproductive cloning is the process of producing a genetically identical copy—a clone—of an entire organism. While clones can be produced by splitting an early embryo—similar to what happens naturally with identical twins—cloning of adult animals is usually done by a process called somatic cell nuclear transfer (SCNT).
Somatic Cell Nuclear Transfer
In SCNT, an egg cell is taken from an animal and its nucleus is removed, creating an enucleated egg. Then a somatic cell—any cell that is not a sex...
Somatic Cell Nuclear Transfer
In SCNT, an egg cell is taken from an animal and its nucleus is removed, creating an enucleated egg. Then a somatic cell—any cell that is not a sex...
01:29Life Histories
Constrained by limited energy and resources, organisms must compromise between offspring quantity and parental investment. This trade-off is represented by two primary reproductive strategies; K-strategists produce few offspring but provide substantial parental support, whereas r-strategists produce much progeny that receives little care. These strategies are related to an organism’s survival likelihood across its lifespan, which is represented by a survivorship curve. Three general types of...
00:51Energy Budgets and Reproductive Strategies
Organisms must balance energy intake with the energy required for growth, maintenance, and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species reproduce only once in their lifetime, often investing most available resources into that single reproductive event. Iteroparous species, by contrast, reproduce multiple times over their lifetimes, typically allocating fewer resources to any single...
01:25Inheritance
Gregor Mendel's pioneering work on the principles of inheritance fundamentally transformed our understanding of how traits are transmitted from generation to generation. His experiments with pea plants laid the groundwork for the discovery of genes, discrete units within organisms that control heredity.
Each gene exists in pairs, and the combination of these genes from both parents forms an individual's genotype. This genotype is a blueprint of potential traits. Examples of genotype traits...
Each gene exists in pairs, and the combination of these genes from both parents forms an individual's genotype. This genotype is a blueprint of potential traits. Examples of genotype traits...
01:30Biological Influences on Intelligence
Intelligence is often thought to be linked to brain size, but the relationship is more complex than that. While brain size does correlate modestly with some abilities, like verbal skills, the connection is weaker for others, such as spatial reasoning. Other factors, like brain structure, also play crucial roles. For instance, despite Einstein's smaller-than-average brain, his parietal cortex, which is involved in spatial reasoning, was 15% wider, suggesting that neural density might matter more...
01:29Environmental Influences on Intelligence
Despite the strong genetic influence on traits like intelligence, environmental factors significantly shape outcomes. For example, while over 90% of height variation is due to genetic differences, environmental factors such as nutrition also have a notable impact. Similarly, for intelligence, changes in a child's surroundings can significantly alter their IQ. Research shows that enriched environments boost children's academic success and help them develop key cognitive skills. Children from...