Question

5. Feral pigeons (Columba livia domestica) have long been considered the most frustrating pest bird. Flocks of these pigeons pose a threat to crops, livestock, and human health as their large numbers can decimate crops and act as disease vectors for pathogens that affect both livestock and humans. However, in places like New York's Washington Square Park, pigeons are well-loved and well-fed members of the community. Controlling these pigeon populations has been a challenge as the mass killings, starving, or poisoning of flocks have been met with public outrage. Researchers set out to find a more humane way of controlling feral pigeon populations, and settled on using nicarbazin bait. Nicarbazin is an avian contraceptive that decreases egg viability by binding to the ZP-3 sperm receptor and decreasing the chances of fertilization. ZP-3 is the receptor that binds the sperm to the surface of the egg at the beginning of fertilization. Nicarbazin has been used successfully to control feral pigeon populations for years. A Nicarbazin-baited population in Washington Square Park displayed a rise in flock numbers, leading researchers to explore the levels of egg viability in the treated populations. They discovered that some birds are affected by the nicarbazin as expected, they produce few viable eggs. However, other birds are producing nearly all viable eggs. Upon further investigation, reproductive researchers have found a mutant allele that alters the shape of ZP-3 receptor and influences the effects of nicarbazin. The mutant allele, Z, at this locus is dominant over the P allele and female pigeons homozygous for Z have the highest egg viability. Pigeons that are heterozygous for this gene have medium egg viability. As part of your summer internship with these researchers, you categorize the 100 female birds in the study population. You count 20 females with high egg viability and 60 females with low egg viability, the rest are in between.
How to complete this table ZZ represents p2, PP represents q2 and ZP represents 2pq.

Answer 1

ZZ individuals have highest egg viability. Number 20

ZP individuals have intermediate egg viability.Number=100-(60+20)=20

PP individuals have low egg viability. Number =60

One individual has two alleles.

Please look in the table;

# individuals # Z alleles #Palleles #alleles Genotypic Frequency ZP 20 0.2 140 40. 0 40 20 0.2 20 20 40 60 | 0.6 | 60 160 120 100 1.0 100 100 200 PP Total

C) The allelic frequentcy for Z allele is 0.3

Genotypic frequency of ZZ + (1/2)× genotypic frequency of ZP= 0.2 +(1/2)×0.2= 0.3

Allelic frequency of P is 1- Z=1-0.3=0.7